# Projects Awarded under PRACE Project Access – Call 21

On this page you will find the projects that were awarded under Call 21c for Proposals for PRACE Project Access in October 2020.

## Biochemistry, Bioinformatics & Life Sciences

Project Leader: Dr. Yolanda Prezado, Centre National de la recherche Scientifique, France

Resource Awarded

• 16 200 000 core hours on Joliot-Curie (SKL) hosted by GENCI at CEA, France

Research Field: Biochemistry, Bioinformatics & Life Sciences

Collaborators

• Ludovic De Marzi, Institut Curie, France
Rachel Delorme, Centre national de la recherche scientifique, France
• Ramon Ortiz Catalan, Centre National de la recherche Scientifique, France
• Marios Sotiropoulos, Centre National de la recherche Scientifique, France
• Thongchai Massilela, Centre National de la recherche Scientifique, France

Abstract

Radiotherapy (RT) is one of the most frequently used methods for cancer treatment (above 50% of patients will receive RT). Despite remarkable advancements, the normal tissues tolerances continue being the main limitation in RT, still compromising an efficient treatment of radioresistant tumors (i.e. gliomas) or paediatric cancers. To overcome this limitation, we propose a new approach, charged minibeam radiation therapy (hMBRT), which partners the normal tissue sparing of submillimetric, spatially fractionated beams with the improved dose deposition of ions. Along this line, proton minibeam radiation therapy has already shown a remarkable reduction of neurotoxicity and an important widening of the therapeutic window for high-grade gliomas in small animal experiments. To prepare phase I/II clinical trials, we need to use Monte Carlo (MC) simulations and HPC to optimise the minibeam generation and to develop a suitable dose calculation engine for patients. In parallel, we aim at extending those methods to heavy ions but as well to very high energy electrons. The small field sizes used require important calculation resources. Only HPC will allow us to perform these calculations.

Project Title: LIPMOD – Lipid modulation of membrane protein functional cycle

Project Leader: Prof Lucie Delemotte, KTH, Sweden

Resource Awarded

• 70 000 000 core hours on Piz Daint hosted by CSCS, Switzerland

Research Field: Biochemistry, Bioinformatics & Life Sciences

Collaborators

• Erik Lindahl, Stockholm university, Sweden
• Rebecca J Howard, Stockholm university, Sweden
• Koushik Choudhury, KTH, Sweden
• Cathrine Bergh, KTH, Sweden
• Yuxuan Zhuang, Stockholm university, Sweden
• Akshay Sridhar, KTH, Sweden
• Annie Westerlund, KTH, Sweden
• Oliver Fleetwood, KTH, Sweden
• Sergio Perez Conesa, KTH, Sweden

Abstract

Membrane proteins such as ion channels, G-protein coupled receptors (GPCRs) and transporters enable cellular communication and, as such, are crucial components of cellular biology. They are also important drug targets, since they are easily accessible to the extracellular medium. Membrane proteins are embedded in a complex lipidic environment, made mainly of a lipid bilayer and other membrane proteins. Whereas early models largely considered the membrane as an inert solvent, it has become increasingly clear that lipid composition and interactions can finely tune protein function. Interestingly, many drugs such as local anaesthetics or steroids modulate the function of these proteins via the membrane, making it important to understand precisely the role played by the membrane in supporting and regulating membrane protein function. Using high performance computing, we will characterize the conformational ensemble of ion channels from two families. Considering different lipid composition as well as the presence lipophilic drugs will enable us to describe the effect of these molecules on the functional states along the conformational cycle, identify state-dependent details of their binding modes and propose models of their mode of action.

Project Title: HA0RES – Mechanisms of mutation resistance in hemagglutinin: Is the uncleaved form HA0 the right target?

Project Leader: Dr. Tiziana Ginex, Centro de Investigaciones Biológicas – Consejo Superior Investigaciones Científicas, Spain

Resource Awarded

• 42 300 000 core hours on Hawk hosted by GCS at HLRS, Germany

Research Field: Biochemistry, Bioinformatics & Life Sciences

Collaborators

• F. Javier Luque, University of Barcelona, Spain

Abstract

Each year, influenza A and B viruses are responsible for 3-5 million severe cases and 290,000-650,000 deaths worldwide. This threatening scenario highlights the need for new therapeutic approaches. One of these promising strategies is Hemagglutinin (HA). HA is a key protein for the entry of the virus in the cell. While previous efforts have targeted the active, fusion-competent species, we hypothesize that resistant mutations may also act at the level of the inactive, fusion-incompetent (‘uncleaved’) form (HA0). In particular, preliminary data suggest that some mutations may promote instability at the cleavage site of HA0, enhancing its susceptibility to proteases and hence HA activation. In this context, an antiviral strategy based on small compounds that inhibit the conformational transition of the cleavable peptide in HA0 might be effective to prevent its activation. Taking advantage of high-performance computing resources, a mapping of the structural and energetic changes required for the conformational rearrangement of the cleavable peptide in HA0 might be useful to design novel HA inhibitors. This study will shed light on a new, yet unexplored, target for antiviral therapy against influenza A. The results might also disclose novel strategies against the spike protein in the current Covid-19 pandemic.

Project Title: FATstor – The role of Bernardinelli-Seip congenital lipodystrophy type 2 protein (BSCL2 – seipin) and its pathological variants in intracellular fat accumulation.

Project Leader: Prof. Stefano Vanni, University of Fribourg, Switzerland

Resource Awarded

• 68 000 000 core hours on Piz Daint hosted by CSCS, Switzerland

Research Field: Biochemistry, Bioinformatics & Life Sciences

Collaborators

• Valeria Zoni, University of Fribourg, Switzerland
• Pablo Campomanes, University of Fribourg, Switzerland
• Josephine Sala, University of Fribourg, Switzerland
• Taraknath Mandal, University of Fribourg, Switzerland

Abstract

Lipid Droplets (LD) are intracellular organelles that are responsible for intracellular fat accumulation. As such, they are crucially involved in metabolic diseases such as lipodystrophy and obesity. Obesity is a particularly serious health concern because of its prevalence, its predisposition to serious illnesses such as metabolic syndrome, diabetes and heart disease, and its role as a risk factor in several pathologies, including viral infections such as flu or COVID-19. Recently, Bernardinelli-Seip congenital lipodystrophy type 2 protein (BSCL2 – seipin), a well-established crucial protein in fat accumulation and LD homeostasis, has been shown to mark the sites of LD formation in the endoplasmic reticulum (ER), and the oligomeric structure of its luminal part has been solved at 3.8 Angstrom resolution using cryo-electron microscopy. These findings pave the way for a molecular understanding of the process of fat accumulation and LD formation in mammalian cells and they offer great promise in the development of therapeutic strategies against mis-regulated fat accumulation in cells and tissues. In this project, we plan to use large-scale coarse-grain (CG) molecular dynamics (MD) simulations to investigate the mechanistic role of seipin in LD formation. Building from our recent experience in modeling LD biogenesis in protein-free lipid bilayers, we will reconstitute in silico the mechanism of LD formation by seipin at physiologically-relevant scales. In our investigations, we will specifically focus on the identification of protein residues and membrane lipids that play a crucial role in this process. Our results will provide a molecular explanation for the known disease-causing variants of seipin and will help identifying new strategies to interfere with LD formation in both physiological and pathological conditions.

Project Title: Pharmacological targeting of NSD2 PHDvCHCH domain: a therapeutic approach against Multiple Myeloma

Project Leader: Dr. Giovanna Musco, Fondazione Centro San Raffaele, Italy

Resource Awarded

• 45 000 000 core hours on Marconi100 hosted by CINECA, Italy

Research Field: Biochemistry, Bioinformatics & Life Sciences

Collaborators

• Andrea Berardi, Fondazione Centro San Raffaele, Italy
• Federico Ballabio, Fondazione Centro San Raffaele, Italy
• Michela Ghitti, Fondazione Centro San Raffaele, Italy

Abstract

Overexpression of the histone methyltransferase NSD2 in multiple myeloma (MM) patients positive to translocation t(4;14), appears to be the driving factor in the pathogenesis of this subtype of myeloma. NSD2 is defined by a catalytic SET domain, two PWWP and six PHD finger domains. Uncontrolled overexpression of NSD2 results in the global reduction of a specific repressive chromatin mark with a de-repression of normally silenced oncogenes, herewith triggering tumorigenesis pathways. Even though the histone methyltransferase activity of NSD2 is fundamental for its oncogenic potential, several evidences suggest that its transcriptional activity also depends on its non-catalytic domains. Indeed, deletion of its tandem PHD finger domain (PHDv-C5HCH NSD2) is associated in strongly reduced oncogene activation and reduced MM cell proliferation. The PHD finger domain is also supposed to be involved in the recruitment of NSD2 complex on repressed chromatin, herewith contributing to the reduction of a specific repressive chromatin mark. However, the molecular mechanisms through which PHDv-C5HCH NSD2 contributes to chromatin recognition and tumorigenesis activation are still unknown. In our lab we are performing biophysical and biochemical experiments (NMR, ITC) to structurally and functionally describe the main characters involved, and we are identifying compounds able to reduce the tumorigenic potential of NSD2 in MM through virtual screening and in vitro binding assays. Besides these approaches, we will take advantages of enhanced molecular dynamics simulations to investigate at atomistic level the interaction between the PHD finger domain and a specific histone tail with different chromatin marks, with particular focus on the molecular signal that we consider highly involved in de-repression of usually silenced oncogenes. The initial step of our computational approach consists of long conventional, all-atom, unbiased molecular dynamics (MD) simulations in explicit solvent, required to retrieve informative collective variables (CVs). Then the CVs will be analysed in combination with multi-replica Parallel Bias Metadynamics (PBMetaD), to speed up the convergence time of the calculation. At the end, after a proper reweight of the CVs, the convergence of the results will be evaluated through the block analysis. The simulations will be performed with GROMACS and PLUMED.

Project Title: ParBigMen: ParSMURF application to Big genomic and epigenomic data for the detection of pathogenic variants in Mendelian diseases

Project Leader: Prof. Giorgio Valentini, Università degli Studi di Milano, Italy

Resource Awarded

• 50 000 000 core hours on SuperMUC hosted by GCS at LRZ, Germany

Research Field: Biochemistry, Bioinformatics & Life Sciences

Collaborators

• Tiziana Castrignanò, University of Tuscia, Italy
• Peter Robinson, The Jackson Laboratory for Genomic Medicine, United States
• Marco Frasca, Università degli Studi di Milano, Italy
• Elena Casiraghi, Università degli Studi di Milano, Italy
• Sara Bonfitto, Università degli Studi di Milano, Italy
• Alessandro Petrini, Università degli Studi di Milano, Italy

Abstract

One of the major problems in the context of Precision Medicine is the lack of a molecular diagnosis for about 50% of the about 8000 known genetic Mendelian diseases. We very recently proposed parSMURF, a hyper-ensemble of learning machines that achieved excellent results in the prediction of pathogenic genetic variants associated with Mendelian and common genetic diseases. The effectiveness of parSMURF strongly depends a) on the fine tuning of its learning parameters and b) on the genomic and epi-genomic features used to train the hyper-ensemble. In this PRACE project we plan to finely tune the learning parameters of parSMURF and to experiment with a huge set of genomic and epi-genomic features downloaded from ENCODE, USCS Genome and other available public repositories, in order to achieve a breakthrough in the discovery of novel pathogenic variants associated with Mendelian diseases. Since both tasks a) and b) require a sheer amount of computing power, this project will be feasible only having access to relevant Tier-0 HPC resources. We expect to achieve breakthrough results in the prediction of Mendelian pathogenic variants, and to embed parSMURF into Genomiser, the state-of-the-art tool for the molecular diagnosis of Mendelian diseases, in collaboration with the US Jackson Lab.

Project Title: TRPs – Structure-based characterization of novel TRPV inhibitors

Project Leader: Prof. Carmen Domene, University of Bath, United Kingdom

Resource Awarded

• 71 000 000 core hours on Piz Daint hosted by CSCS, Switzerland

Research Field: Biochemistry, Bioinformatics & Life Sciences

Collaborators

• Simone Furini, University of Siena, Italy
• Alex Peralvarez Marin, Universitat Autònoma de Barcelona, Spain
• Alexander Mackerell, University of Maryland, United States

Abstract

Transient receptor potential (TRP) ion channels enable us to sense mechanical, thermal and chemical stimuli. In particular, they are involved in the perception of cold and hot and pain, and thus, constitute an attractive pharmacological target. Consequently, understanding the chemical regulation of TRP channels is essential for the development of analgesic drugs. The recent availability of the three-dimensional structure of several of these ion channels has provided an excellent opportunity to start understanding at an atomistic level how these biomolecules work. In particular, we are interested in the TRPV family composed by six members. Despite their relevance, the molecular determinants involved in their activation remain elusive.

Project Title: Combining Deep Learning and Language Modelling Techniques to improve prediction of bioactive peptides from natural sources

Project Leader: Mr. Hansel Gomez, NURITAS Ltd., Ireland

Resource Awarded

• 68 000 000 core hours on Piz Daint hosted by CSCS, Switzerland
• HLST Support

Research Field: Biochemistry, Bioinformatics & Life Sciences

Collaborators

• Alessandro Adelfio, NURITAS Ltd., Ireland
• Niall Murphy, NURITAS Ltd., Ireland
• Piero Conca, NURITAS Ltd., Ireland

Abstract

Bioactive peptides (BPs) are protein fragments that can have a positive impact on body functions through specific protein-protein interactions (PPIs). BPs are known to modulate the digestive, endocrine, cardiovascular, immune and nervous systems. Moreover, they can prevent oxidation and microbial degradation in foods. Unsurprisingly, BPs have drawn the attention of the scientific community, and indeed the pharmaceutical industry, which for decades had been focused primarily on small molecule drugs. There are many advantages of BPs over the former. Firstly, due to the nature of PPI interfaces, which are dominated by large contact areas (i.e. 1500-3000 A2), BPs are more efficient and specific than other drug molecules that typically target small, well-defined protein pockets. A typical PPI interface is constituted by multiple ‘hot spots’ or important interaction sites spread throughout the binding surface, which account for most of the interaction energy. In such cases, only molecules with big contact areas, such as peptides, can achieve nanomolar potency at the PPI interface. Moreover, the high selectivity of BPs translates into fewer off-target side effects than small molecule drugs. BPs degrade into amino acids thus minimizing the risk of toxicity. Furthermore, peptide therapeutics are typically associated with lower production complexity and therefore reduced costs. Finally, the chemical and physical stability, circulating plasma half-life, and cell-penetrating properties of BPs can be appropriately improved through various engineering processes. Some BPs occur endogenously in nature; however, the vast majority are encrypted within the structure of parent proteins and so need to be unlocked via hydrolysis to release their activity. Founded in 2014, Nuritas is a biotechnology company that uses AI to predict bioactive peptides from natural food sources that can be used in therapeutic and preventative fields. The company’s unique, disruptive computational approach to therapeutic discovery uses artificial intelligence, deep learning and genomics to rapidly and efficiently predict and then unlock peptides, with peptide predictions validated in-house by our multidisciplinary team of laboratory scientists. The core of Nuritas relies on machine learning (ML); including Natural Language Processing (NLP) to extract information from scientific literature, state-of-the-art models to predict peptide bioactivity, in addition to techniques such as image processing and graph representation. Our main goal for using the PRACE facilities is to develop new NLP-based machine learning models that incorporate more advanced and complex embedding techniques to increase the predictive power of our predictors and therefore identify novel BPs from natural sources.

Project Title: MEMREP: Multi-scale simulations of annexin-mediated membrane repair mechanisms and of strategies to undermine membrane repair in cancer cells

Project Leader: Dr. Himanshu Khandelia, University of Southern Denmark, Denmark

Resource Awarded

• 56 700 000 core hours on Marconi100 hosted by CINECA, Italy

Research Field: Biochemistry, Bioinformatics & Life Sciences

Collaborators

• Vikas Dubey, University of Southern Denmark, Denmark
• Ali Zanjani, University of Southern Denmark, Denmark
• Maria Karlsen, University of Southern Denmark, Denmark
• John Ipsen, University of Southern Denmark, Denmark
• Adam Simonsen, University of Southern Denmark, Denmark
• Jesper Nylandsted, Danish Cancer Society Research Center, Denmark
• Poul Martin Bendix, University of Copenhagen, Denmark
• Weria Pezeshkian, University of Groningen, Netherlands
• Mayank Prakash Pandey, University of Southern Denmark, Denmark

Abstract

The plasma membranes (PM) of cancer cells are under intense rupture stress due to increased metabolic and cell division rates, and the increased membrane dynamics resulting from invasive behaviour through dense extracellular matrix. To maintain membrane integrity, cancer cells overexpress plasma membrane repair machinery, which all eukaryotic cells employ to cope with membrane disruptions. Members of the annexin (ANXA) protein family are Ca+2-sensitive phospholipid-binding proteins that initiate and regulate membrane repair. Dysregulated PM repair is also involved in other diseases such as muscular dystrophies and Chediak-Higashi syndrome. Despite the essential function of membrane repair in maintaining cell survival, PM repair mechanisms in healthy and diseased cells remain poorly understood. Using large-scale molecular simulations on HPC systems, we aim to elucidate fundamental biophysical mechanisms of plasma membrane repair with particular focus on the disruption of these repair mechanisms in cancer cells. We expect to improve our understanding of how ANXAs repair membranes lesions, and how such repair mechanisms can be compromised in cancer cells using small molecules that inhibit ANXA mediated repair, potentially leading to unique anticancer treatments. The proposed project is a close collaboration with a funded consortium comprising of three other experimental groups in biophysics and cancer biology in Denmark.

## Chemical Sciences & Materials

Project Title: DIMAB – DIslocations in bcc Metals: an AB initio study

Project Leader: Dr Lisa Ventelon, CEA, France

Multi-year Proposal: Year 2

Resource Awarded

• 10 000 000 core hours on JUWELS hosted by GCS at FZJ, Germany

Research Field: Chemical Sciences & Materials

Collaborators

• Lucile Dezerald, Institut Jean Lamour, France
• François Willaime, CEA, France
• David Rodney, Université Claude Bernard Lyon 1, France
• Bassem Ben Yahia, Institut Jean Lamour, France
• Guillaume Hachet, CEA, France
• Emmanuel Clouet, CEA, France

Abstract

The fundamental understanding of metallurgy constitutes an essential aspect in worldwide basic research. Thus it is essential to keep investing in the next generation of metallic alloys, thereby helping tackling some of the societal challenges related to energy, renewables and CO2-reducing technologies. This is the reason why it is of great importance to understand the mechanisms underlying deformation in metals and alloys as a first step for a better apprehension of current material aging as well as for the next step for development of advanced metal-based products. In this context, the understanding of the behavior of metallic structural materials requires the modeling of atomic-scale events and their consequences on mechanical properties, thereby involving coupling between mechanical behavior and atomic bonding down to the electronic structure level. In this framework, the goal of this proposal is to study the link between dislocation core properties and plasticity in metals and alloys using density functional theory (DFT) calculations. Such DFT calculations are extremely computationally demanding but they are necessary to build a complete and physical picture of plasticity in metals and alloys that can serve in turn as input for larger-scale plasticity models such as dislocation dynamics, as well as as an absolute necessary DFT database in order to better train on dislocation geometries promising approaches based on machine learning. The goal of this proposal is to study at the atomic scale the link between screw dislocation core properties and plasticity in metals and alloys using DFT calculations. The first subproject of the first year will focus on the poorly understood phenomenon of anomalous slip in BCC metals, constituting a striking violation of Schmid’s law, using DFT calculations. Comparison between BCC metals, namely Mo, Fe and Nb, as well as comparison with experimental data, will enable understand and predict dislocation anomalous glide in all BCC metals. The second subproject of the first year will focus on the origin at the atomic scale of interstitial solute effects on mechanical properties in metals and alloys, and particularly to study how helium and hydrogen interstitials form atmospheres around dislocations and enhance/impede flow through notably pipe diffusion phenomena. The proposed approach in this project couples ab initio calculations of interaction energies and energy barriers and thermodynamic modeling of solutes and kinks in order to describe the dislocation glide mechanisms in the presence of helium and hydrogen solutes. The second year will be devoted to very innovative calculations on non-conventional glide in W and W(Re) alloys. The proposed simulations are very computationally demanding and challenging as they will use the Activation Relaxation Technique (ART), which allow the automated search of migration paths in systems of complex configurations. The third year also involves cutting-edge DFT calculations on dislocation-solute interaction in the FeCCr ternary system, where a substantial number of configurations will have to be investigated with carbon interstitial and chromium substitutional solutes interacting together as well as with the dislocation core.

Project Title: OptoSpin – Towards realistic simulation of transition metal dichalcogenide opto-spintronic devices

Project Leader: Prof. Matthieu Verstraete, University of Liège, Belgium

Multi-year Proposal: Year 1

Resource Awarded

• 40 000 000 core hours on MareNostrum 4 hosted by BSC, Spain

Research Field: Chemical Sciences & Materials

Collaborators

• Joao Carlos Correia de Abreu, University of Liège, Belgium
• Bertrand Dupe, University of Liège, Belgium
• Patrick Buhl, Johannes Gutenberg University of Mainz, Germany
• Samuel Ponce, École Polytechnique Fédérale de Lausanne, Switzerland
• Alexandre Heuchamps, University of Liège, Belgium
• Pedro Miguel MONTEIRO CAMPOS DE MELO, University of Liège, Belgium
• Thibault Sohier, University of Liège, Belgium
• Francesco Macheda, King’s College London, United Kingdom
• Zeila Zanolli, University of Utrecht, Netherlands
• Nils Wittemeier, ICN2, Spain
• Jinxuan Yoou, SIMUNE Atomistics Simulations, Spain

Abstract

Continuous advancements in technology have led us to increasingly small devices, closely approaching the nanoscale. However, it is at this scale that silicon reaches its limit thus posing a great challenge to further technological developments. One of the most promising solutions to overcome this difficulty is to turn to two dimensional materials. This large family of materials offers a versatile solution with rich properties, from insulators to conductors, magnets and superconductors. In this project, we exploit state-of-the-art first-principles methods and HPC resources, to understand and control the key parameters involved in the design of next-generation opto-spintronics devices. While most of today’s electronics is based on the electron’s charge, other degrees of freedom like the spin magnetic moment or excitons promise more energy-efficient operation and finer manipulations. Transition-metal dichalcogenides (TMDs) open new avenues for the electrical and optical control of charge, within a single class of materials, generating much excitement in the community. This stems from a combination of physical properties that, in addition to their own complexity, depend strongly on their environment. We will begin by examining the intrinsic properties of the 15 most popular TMDs, and other promising 2D materials identified by high throughput searches. We will then investigate the most promising candidates under realistic conditions including defects, encapsulation and field-effect doping. At every step, we compute figure-of-merit quantities for charge and spin transport, as well as optical control. This project will bridge a gap between fundamental and applied aspects of TMD physics, by providing reliable design guidelines concerning the composition and quality of the operating material, as well as its environment within a device.

Project Title: NAUTILUS – eNergy scAvenging by liqUid inTrusIon in Lyophobic poroUs Systems

Project Leader: Dr. Simone Meloni, University of Ferrara, Italy

Multi-year Proposal: Year 1

Resource Awarded

• 47 000 000 core hours on Marconi100 hosted by CINECA, Italy

Research Field: Chemical Sciences & Materials

Collaborators

• Antonio Tinti, Sapienza University of Rome (IT), Italy
• Sebastiano Fabio Schifano, University of Ferrara, Italy
• Marco Tortora, Sapienza University of Rome (IT), Italy
• Carlo Guardiani, Sapienza University of Rome (IT), Italy
• Alberto Giacomello, Sapienza University of Rome (IT), Italy

Abstract

This project aims at investigating the intrusion/extrusion mechanism, energetics and kinetics of liquids from porous materials, namely metal-organic frameworks (MOF). This process has potential applications in many fields and, among the others, for energy scavenging, converting dissipated mechanical energy used to trigger intrusion into electric current via a liquid/solid electrification phenomenon recently discovered by a partner experimental group. The objective of our simulations is to identify the relation between the chemical and morphological properties of MOFs and liquids of the characteristics of intrusion. This will allow us to discover design or selection principles to identify the ideal material, with adequate pressure-volume intrusion/extrusion cycle showing a pronounced hysteresis, which sets the maximum amount of mechanical energy that can be transformed in electric current per intrusion/extrusion cycle. Also important is the absolute value of the intrusion and extrusion pressure, which must be within the range of the mechanical input triggering intrusion. On top of this, given the interest on MOFs for a broad range of applications, going from chemistry, where, e.g., these materials can be used for catalysis thanks to their large contact area, physics, in which MOFs are considered, for example, to study the peculiar properties of highly confined molecular or liquid systems, medicine, where porous systems can be exploited for specific and controllable drugs release, and engineering, for nanofluidics, we expect that the finding of our project can have an impact on many disciplines.

Project Title: PCETdynamics

Project Leader: Prof. Ville Kaila, Stockholm Univeristy, Sweden

Resource Awarded

• 33 700 000 core hours on MareNostrum 4 hosted by BSC, Spain

Research Field: Chemical Sciences & Materials

Collaborators

• Ana Gamiz-Herandez, Stockholm Univeristy, Sweden
• Patricia Saura, Stockholm Univeristy, Sweden
• Andrea Di Luca, Stockholm Univeristy, Sweden
• Dirk Auman, Stockholm Univeristy, Sweden
• Daniel Riepl, Stockholm Univeristy, Sweden
• Maximilian Pöverlein, Stockholm Univeristy, Sweden
• Friederike Allgöwer, Stockholm Univeristy, Sweden
• Hyunho Kim, Stockholm Univeristy, Sweden
• Louis Cochen, Stockholm Univeristy, Sweden
• Alexander Jussupow, Technische Universität München, Germany
• Michael Röpke, Technische Universität München, Germany
• Sophie Mader, Technische Universität München, Germany
• Max Mühlbauer, Technische Universität München, Germany

Abstract

All organisms capture chemical or light energy and transduce this into forms that power their energy metabolism. On a molecular level, these processes are catalyzed by membrane-bound redox-enzymes that pump protons across a biological membrane. In this project we study the structure, dynamics, and function of respiratory complex I using large-scale molecular simulations. Complex I is a gigantic (1 MDa) membrane-bound enzyme that functions as the primary energy conversion machinery in mitochondrial respiratory chains. Recent structural data have provided molecular insight in its overall architecture, but it still remains unknown how complex I pumps protons across large molecular distances of > 200 Å. By combining classical and hybrid QM/MM molecular dynamics simulations with data from recent cryo-EM experiments, we study here the long-range charge transfer dynamics in the mitochondrial complex I, that remains a hotly debated topic in modern biochemical research. This highly efficient proton-coupled electron transfer (PCET) reaction provides a unique example of action-at-a-distance effects in biology, with important implication for developing new energy technology. Moreover, dysfunction of complex I is linked to about half of all human mitochondrial disorders, and understanding its mechanistic principles is thus of profound biochemical and biomedical relevance.

Project Title: Mechanism of the light-driven self-assembly process of the catalytic centre of Photosystem II

Project Leader: Prof. Leonardo Guidoni, Università degli Studi dell’Aquila, Italy

Multi-year Proposal: Year 1

Resource Awarded

• 16 000 000 core hours on Joliot-Curie (KNL) hosted by GENCI at CEA, France

Research Field: Chemical Sciences & Materials

Collaborators

• Daniele Narzi, University of LAquila, Italy
• Matteo Capone, Università degli studi dell’Aquila, Italy
• Giuseppe Mattioli, CNR, Italy
• Mario Frezzini, Università degli studi dell’Aquila, Italy
• Shin Nakamura, Kyusyu University, Japan, Japan
• Aliya Tichengulova, Research Institute of Experimental and Theoretical Physics, Almaty, Kazakhstan, Kazakhstan

Abstract

Since about three billion years, water oxidation occurring in the first steps of the natural oxygenic photosynthesis is catalysed by the protein/pigment complex Photosystem II (PSII). The catalytic centre of such complex includes the Mn4Ca cluster where the water splitting reaction takes place, resulting in the production of electrons, protons and molecular oxygen. The catalytic mechanism consists of five S0 – S4 subsequent steps, known as Kok-Joliot cycle [14], during which four electrons and four protons are extracted from two water molecules until the formation and release of molecular oxygen. Despite the recent successes in the characterization of the water splitting mechanism catalysed by PSII, much less is known about the light-drive self-assembly process of the Mn4Ca cluster in PSII. This process, also known as photoactivation, represents a key process in Nature, being it crucial in both initial activation and continuous repair of the natural water-oxidation catalysts Photosystem II (PSII) following to light-induced irreversible damage. Despite different kinetic and structural experiments have been carried out in order to characterize the photoactivation process, the mechanism of the light-driven self-assembly of Mn4Ca cluster in PSII is still largely unknown. Understanding the molecular details of the photoactivation process has important implications in different fields, e.g. helping to identify the evolutionary route towards the present reaction centre of PSII; shedding light on the origin of geologic Mn deposits from the early Paleoproterozoic; helping the development of plants with improved growth characteristics; suggesting synthesis and repair strategies for artificial photosynthesis devices. The present project has the purpose to characterize, by means of classical and QM/MM MD simulations, and Minimum-Energy-Path calculations, the mechanism of the self-assembly process of the manganese cluster in both water solution and apo PSII. We will perform classical MD simulations of the apo PSII (i.e. Mn4Ca depleted PSII) considering different possible protonation states of the titratable residues in the task of Mn4Ca, thus determining the most likely protonation patterns and the arrangement of water molecules in the task. Such simulations, repeated in the presence and absence of the Ca2+ ion, whose timing of its inclusion in the task is not yet experimentally resolved, will be used as starting points for subsequent QM/MM MD simulations in which one or two Mn2+ ions will be included in different positions. Finally, starting from snapshots extracted from QM/MM MD simulations, we will employ Minimum-Energy-Path (MEP) calculations in order to characterize the energetics of the Mn–oxo–Mn and Mn–oxo–Ca formations. Moreover, in the first part of the project, parallelly to classical MD simulations, we will carry out MEP calculations of Mn – oxo – Mn and Mn – oxo – Ca formation in pure water and in water with presence of phosphate counterions. These calculations will represent a valuable benchmark to understand how the protein environment can facilitate the self-assembly process of the Mn4Ca cluster

Project Title: Electrochemical water splitting at the Pt/electrolyte double layer from ab initio molecular dynamics

Project Leader: Dr. Clotilde Cucinotta, Imperial College London, United Kingdom

Resource Awarded

• 35 100 000 core hours on SuperMUC hosted by GCS at LRZ, Germany
• HLST Support

Research Field: Chemical Sciences & Materials

Collaborators

• Federico Raffone, Imperial College London, United Kingdom
Marialore Sulpizi, johannes gutenberg universitat mainz, Germany

Abstract

Water electrolysis plays an essential role in a great number of electrochemical processes that involve the coupled transfer of protons and electrons and is a fundamental step for energy production. In our project we plan to investigate water electrolysis at the Pt/water electrolyte interface in realistic operando conditions, with first principles molecular dynamics (MD) simulations. More specifically, after an initial calibration of the ab initio MD approach, we will address the following milestones over a two years period: i. detailed characterization of the equilibrium nano-structure of the double layer at the Pt/water electrolyte interface, as a function of the applied voltage; ii. relaxation, reconstruction and coverage of the metal surface when polarized and analysis of the chemical composition of the water layer in contact with the metal; iii. study of the effect of the presence different ions in solution on the interfacial nano-structure and charge distribution as well as the competition between the adsorption of selected ions and H on the metal surface; iv. investigation of the rate for half-redox reactions at the Pt electrode, which is related with the overpotential; v. determination of the water stability window on Pt. From a computational point of view, the project entails a massive and challenging computation, requiring and exploiting in full the efficiency of the CP2K package, as well as the power of the most recent PRACE infrastructure, i.e., the new German HPC cluster, Hawk.

Project Title: ELGEN – The electronic-structure genome of materials

Project Leader: Prof Nicola Marzari, EPFL, Switzerland

Resource Awarded

• 70 000 000 core hours on Piz Daint hosted by CSCS, Switzerland

Research Field: Chemical Sciences & Materials

Collaborators

• Giovanni Pizzi, EPFL, Switzerland
• Sebastiaan Huber, EPFL, Switzerland
• Marnik Bercx, EPFL, Switzerland
• Marco Borelli, EPFL, Switzerland

Abstract

The electronic band structure of materials drives some of the most crucial scientific and technological characteristics and applications. These include the capability to harvest sunlight for electricity in photovoltaic materials or to drive fundamental redox reactions – from water splitting to CO2 reduction to water purification to fine-chemicals production. Other examples are the intrinsic mobility of electronic devices, the figure of merit of thermoelectric converters, the transition temperature of superconductors, the protected electronic structure of topological insulators. This project aims to 1) calculate with predictive accuracy the electronic band structures of an extensive, varied, and comprehensive reference database of experimentally known inorganic materials, using a hierarchy of electronic-structure approximations that ultimately deliver the accuracy needed to predict novel materials of outstanding scientific or technological relevance, and to 2) apply it to identify novel materials with great promise in photocatalytic and thermoelectric applications, or displaying robust topological states for information-and-communication technologies. The project is driven by our capabilities in GPU-based high-performance and high-throughput computing; in the open dissemination of data and results; and in the capability to encode automatically and exactly any electronic band structure into the optimal reduced basis set of maximally localized Wannier functions.

Project Title: Anchoring molecular catalysts on a surface: advancing artificial water reduction

Project Leader: Prof. Dr. Sandra Luber, University of Zurich, Switzerland

Resource Awarded

• 5 200 000 core hours on JUWELS Booster hosted by GCS at FZJ, Germany

Research Field: Chemical Sciences & Materials

Collaborators

• Edward Ditler, University of Zurich, Switzerland

Abstract

Solar light-driven water splitting to produce molecular hydrogen represents a promising and sustainable way of fuel production. For this purpose, efficient and stable water oxidation and reduction catalysts are needed. Particularly, new ligand frameworks based on (poly-)pyridyl moieties can exhibit high activity not only in homogeneous solution, but also when adsorbed on metal oxide nanoparticles, which is attractive for large-scale water splitting applications. Phosphonate groups attached to a metal complex via a linker have been routinely used for the immobilization of molecules on metal oxide surfaces. Little is known about the exact mechanism by which the anchoring groups bind to surfaces, although they are of high interest for various processes. Within the proposed project, we plan to make an important step towards the in-depth description of the binding modes of anchoring groups on a functional surface in solution. A combination of both static and forefront dynamic density functional theory (DFT)-based simulations will provide insight into the complex solvent-solute-substrate interactions at an interface and pave the way for informed design propositions towards more stable and efficient H2 generating systems.

## Earth System Sciences

Project Title: Local Probabilistic Tsunami Hazard Assessment for HPC – TsuHazAP

Project Leader: Dr. Finn Løvholt, Norwegian Geotechnical Institute, Norway

Resource Awarded

• 70 000 000 core hours on Marconi100 hosted by CINECA, Italy

Research Field: Earth System Sciences

Collaborators

• Jorge Macias, Universidad de Málaga, Spain
• Manuel J. Castro Diaz, Universidad de Málaga, Spain
• Carlos Sánchez Linares, Universidad de Málaga, Spain
• Marc de la Asunción Hernández, Universidad de Málaga, Spain
• Jacopo Selva, Instituto Nazionale di Geofisica e Volcanologia (INGV), Italy
• Stefano Lorito, Instituto Nazionale di Geofisica e Volcanologia (INGV), Italy
• Manuela Volpe, Instituto Nazionale di Geofisica e Volcanologia (INGV), Italy
• Steven Gibbons, Norwegian Geotechnical Institute, Norway
• Sylfest Glimsdal, Norwegian Geotechnical Institute, Norway
• Malte Vöge, Norwegian Geotechnical Institute, Norway
• Roberto Tonini, Instituto Nazionale di Geofisica e Volcanologia (INGV), Italy
• Fabrizio Romano, Instituto Nazionale di Geofisica e Volcanologia (INGV), Italy
• Piero Lanucara, CINECA, Italy

Abstract

Probabilistic Tsunami Hazard Analysis (PTHA) quantifies the likelihood of exceeding a specified measure of tsunami inundation at a given location within a given time interval. Previously, PTHA has been either limited to offshore calculations, and high-resolution inundation calculations have been restricted to a reduced set of scenarios. GPU-based codes and Tier-0 facilities now make these inundation calculations feasible. A PTHA workflow has been developed in the EC-funded ChEESE Center of Excellence for Exascale computing. The workflow utilizes the Tsunami-HySEA GPU code for simulating tsunami propagation and inundation on nested topo-bathymetric grids, and local hazard aggregation Through source selection and refinement from an existing coarse-grained regional assessment, applying this workflow will dramatically increase the accuracy of the tsunami hazard through inundation simulations for each scenario. This hazard analysis will require hundreds of thousands of simulations for a single target location. To address the trade-off between number of simulations and uncertainty size, the full range of simulations needs to be performed and then progressively reduced. This can only be accomplished with PRACE-sized resources. This project is further needed to understand how upscaling using Exascale would make high-resolution PTHA more accurate and then feasible as a scientific benchmark for decision-making regarding coastal planning.

Project Title: ASSIM2K – proxy data ASSIMilation and attribution of climate changes during the last 2000 years (2K)

Project Leader: Dr. Myriam Khodri, IRD, France

Multi-year Proposal: Year 1

Resource Awarded

• 40 000 000 core hours on Joliot-Curie Rome hosted by GENCI at CEA, France

Research Field: Earth System Sciences

Collaborators

• Nicolas Lebas, CNRS, France
• Beyrem Jebri, CNRS, France
• Julian VILLAMAYOR MORENO, CNRS, France
• Sébastien Nguyen, CNRS, France
• Arnaud Caubel, CEA, France
• Yann Meurdesoif, CEA, France

Abstract

Proxy records (corals, speleotheme, etc.) documenting the last 2000 years (2K) provide evidences for the wide range of natural variability not captured by recent direct observations. Since anthropogenic forcings are not the only external source influencing internal ocean variability, we need to assess climate models ability to reproduce natural climate variations. ASSIM2K proposes to use a novel cutting edge method to reconstruct and attribute sources of recent climate changes, through the seamless integration across the last 2K of external (natural and anthropogenic) forcings and the assimilation of observations (instrumental and proxy) in the massively parallelized VLR IPSL-CM6 climate model. Relying on the “SIR-LIM” particle filter method we recently developed, which uses a Linear Inverse Model as an emulator of the IPSL model, the trajectory of hundreds of simulations can be optimally guided by proxy records available worldwide. The PRACE allocation will generate breakthrough outcomes allowing (i) benchmark against observations and documented historical events, the ability of CMIP-class climate models to capture the processes of natural climate change, (ii) identify when, where and with which level of confidence anthropogenic climate changes emerge out of the natural “noise” and (iii) compare historical and modern societies resilience to past and recent climate changes.

## Engineering

Project Title: WakePropRudd – Characterization of the wake of a propeller-rudder system

Project Leader: Dr. Riccardo Broglia, National Research Council of Italy, Institute of Marine Engineering, Italy

Resource Awarded

• 73 000 000 core hours on Joliot-Curie Rome hosted by GENCI at CEA, France

Research Field: Engineering

Collaborators

• Antonio Posa, National Research Council of Italy, Institute of Marine Engineering, Italy

Abstract

The interaction between an upstream propeller and a downstream wing or rudder is typical in aeronautical and naval applications. Propellers generate a very complex wake, featuring a wealth of coherent structures, especially the tip and hub vortices, whose evolution is substantially affected by the interaction with downstream appendages. Such interaction increases pressure fluctuations, which define vibrations, cavitation phenomena and the acoustic signature of the overall system. The above phenomena have an adverse impact on the structural integrity of devices (fatigue), the comfort of passengers and crew members on board of ships and airplanes and on the environmental impact of marine and air transportation via noise emission. To date, studies dealing with propeller-rudder interaction are very limited, because of experimental and computational challenges. In particular, numerical simulations require a substantial computational effort to handle bodies in relative motion, achieve high levels of resolution in both space and time, resolve turbulent fluctuations with minimal modeling assumptions and produce a statistical sample large enough to achieve convergence of the statistics of turbulence. In this project we propose high-fidelity computations to capture the complex wake features of a propeller operating upstream of a hydrofoil at incidence, aimed at investigating the impact of this configuration on the topology of the overall wake. Our earlier studies on a similar configuration, but with the downstream hydrofoil aligned with the propeller wake, demonstrated a substantial spanwise shift of both tip and hub vortices. Such shift reinforces their mutual interaction, leading to earlier destabilization and triggering high level of turbulent fluctuations. Downstream of the overall system the wake topology becomes even more complex, since the several components of the wake, especially the branches of the tip and hub vortices coming from the two sides of the hydrofoil and the shear layers shed from the trailing edge of the latter, keep significant values of cross-stream velocity. This promotes further shear, producing a non-monotonic evolution of turbulence, affecting the wake signature of the overall system. The configurations considered in this project introduce significant pressure gradients across the hydrofoil, because of the orientation of the latter at non-zero incidence. Such pressure gradients are expected to produce an even more complex physics and wake signature, mimicking the working conditions of the propeller-rudder system within a scenario of a maneuvering ship. Computations will be carried out using a viscous fluid dynamic solver with optimal conservation properties via a high-fidelity technique (Large-Eddy Simulation, LES), where all important scales of turbulence are fully resolved, instead of being modeled, making the approach also suitable to generate an unprecedented database for future hydro-acoustic studies. The solver has parallel capabilities and its scalability was demonstrated on several distributed memory clusters in the framework of a number of practical flow problems involving turbomachinery, wind turbines and naval hydrodynamics. Results will be compared against those from our earlier studies on the same propeller in isolated conditions and operating upstream of the same hydrofoil at zero incidence, to assess the influence of its incidence angle on the properties of the wake flow.

Project Title: Shock-Wave/Boundary-Layer Interaction with an Elastic Structure

Project Leader: Prof. Dr. Stefan Hickel, Delft University of Technology, Netherlands

Resource Awarded

• 60 000 000 core hours on Hawk hosted by GCS at HLRS, Germany

Research Field: Engineering

Collaborators

• Bas van Oudheusden, Delft University of Technology, Netherlands
• Luis Laguarda Sanchez, Delft University of Technology, Netherlands
• Davide Modesti, Delft University of Technology, Netherlands
• Ferdinand Schrijer, Delft University of Technology, Netherlands

Abstract

Interactions of shock waves with turbulent boundary layers (SWBLI) occur in many high-speed applications, such as on aircraft wings and control surfaces, in engine air intakes and in rocket nozzles. SWBLI have crucial effects on aerodynamic efficiency and system lifetime and uncontrolled SWBLI can even lead to component failure due to vibrational fatigue. The goal of this project is to improve physical models for the low-frequency SWBLI dynamics and for the aeroelastic interaction of SWBLI with structural components at realistic conditions with very high Reynolds numbers. This PRACE project is part of a joint experimental-numerical initiative to characterize SWBLI phenomena with an unprecedented degree of detail at significantly higher Reynolds numbers than in currently available high-fidelity simulations. Aeroelastic effects will be examined by considering rigid and deformable walls. Alongside the numerical work, wind-tunnel experiments will be conducted for the same setup to further improve the quality of our dataset and validate numerical findings. The comprehensive high-quality dataset will be used to scrutinize long-standing paradigms of SWBLI dynamics at realistic conditions including fluid-structure interactions. This novel contribution will help designers to mitigate the impact of SWBLI in high-speed aerodynamics applications.

Project Title: TORNADO – Rotating double diffusive and Rayleigh-Bénard convection

Project Leader: Prof. Roberto Verzicco, Università di Roma Tor Vergata, Italy

Resource Awarded

• 50 000 000 core hours on MareNostrum 4 hosted by BSC, Spain

Research Field: Engineering

Collaborators

• Detlef Lohse, University of Twente, Netherlands
• Richard Stevens, University of Twente, Netherlands
• Chong Ng, University of Twente, Netherlands
• Kai Chong, University of Twente, Netherlands
• Pieter Berghout, University of Twente, Netherlands
• Martin Assen, University of Twente, Netherlands
• Qi Wang, University of Twente, Netherlands
• Robert Hartmann, University of Twente, Netherlands
• Guru Sreevanshu Yerragolam, University of Twente, Netherlands

Abstract

Buoyancy-driven convection exists in many natural environments and is of utmost importance. Common examples are flows in the atmosphere, in the oceans, in the Earth’s mantle, in the Earth’s outer core, in stars, as well as in buildings, and various industrial applications. To get a better understanding of such buoyancy-driven flows, Rayleigh-Bénard convection (RBC) serves as the classical model problem. However, RBC is the flow of a fluid heated from below and cooled from above, and thus describes pure thermally-driven flows only. Yet, in most geophysical phenomena, density too depends on compositional gradients in addition to temperature. Such a flow system driven by two scalar fields is named double diffusive convection (DDC). Examples include thermal convection with compositional gradients in astrophysics, in the solid Earth, and, however most relevant, in the oceans. The seawater density is mainly determined by its temperature and salinity. DDC has been widely observed in the upper water layer of the oceans, and it has been estimated that over 40% of the oceans display DDC. One intriguing phenomenon associated with diffusive DDC is layering and staircase, in which well-mixed convection layers are separated by high gradient sharp interfaces. Such layering and staircases have a vertical length scale of meters, but show very large lateral coherence, i.e. hundreds of kilometres. The physical mechanism of diffusive layering is not fully explained yet. Another factor which is also important in many geophysical convection phenomena is rotation. For example, rotating convection occurs in the ocean, in the liquid metal cores of terrestrial planets, in gas giants, and in rapidly rotating stars. All these systems are highly turbulent, but at the same time Coriolis forces chiefly control their dynamics. In the oceans, rotation is responsible for mechanism like Ekman pumping and Ekman transport or Western boundary currents like the Gulf stream on large scales. Rotating RBC has served as a canonical framework to study rotating convection, and it has attracted lots of attention over the past few years. Studying rotating RBC and rotating DDC thus becomes essential in understanding many of the large-scale fluid phenomena occurring in geophysical and astrophysical systems. Astonishingly, it has been observed that both, rotation as well as a second salar field, by itsself show similar effects on the flow dynamics. The dynamics of the system depends on the driving intensity and the fluid properties, which are characterized, by dimensionless numbers, e.g., the Rayleigh number and the Prandtl number. In this project we want to address two current key questions: (1) What are the physical mechanisms that maximize the heat transport in rotating RBC at high thermal Rayleigh numbers? (2) How are momentum and heat transport, as well as the flow organization in large-scale coherent structures (so-called superstructures) altered by rotation and the ratio between temperature and salinity gradients in rotating DDC?

Project Title: DESTINE (Direct numErical Simulation of Turbulent pipe flow at high Reynolds NumbEr)

Project Leader: Prof. Sergio Pirozzoli, Sapienza University of Rome, Italy

Resource Awarded

• 50 000 000 core hours on Marconi100 hosted by CINECA, Italy

Research Field: Engineering

Collaborators

• Paolo Orlandi, Sapienza University of Rome, Italy
• Roberto Verzicco, University of Twente, Netherlands
• Massimiliano Fatica, NVIDIA Corporation, United States
• Josh Romero, NVIDIA Corporation, United States

Abstract

This research project aims at achieving a major step forward in the direct numerical simulation (DNS) of turbulent pipe flow, by taking the friction Reynolds number from the current state-of-the-art of 3000 to about 8000. Numerical simulations will also include the solution of the transport equation for passive scalars to model heat and mass transfer processes. Studying pipe flow at high Reynolds number allows the observation of physical phenomena of interaction between the near-wall and the outer layers which haven’t been accessed yet in numerical simulation. Pipe flow is ubiquitous in engineering applications, and we expect that additional insight into its basic underlying physics may translate to design of improved techniques for drag reduction and/or heat transfer enhancement.

Project Title: TBLFST – Transition in boundary layers with free-stream turbulence

Project Leader: Prof. Philipp Schlatter, KTH Royal Institute of Technology, Sweden

Resource Awarded

• 78 300 000 core hours on MareNostrum 4 hosted by BSC, Spain

Research Field: Engineering

Collaborators

• Kristina Durovic, KTH Royal Institute of Technology, Sweden
• Ardeshir Hanifi, KTH Royal Institute of Technology, Sweden
• Dan Henningson, KTH Royal Institute of Technology, Sweden

Abstract

Fluid flow around solid bodies has been the subject of active research for many years, driven by the apparent application in aeronautics, vehicle and process industries. Typically, a thin boundary layer forms adjacent to the wall, in which most of the flow drag is produced. The behaviour of these thin layers is thus crucial for the overall performance of such objects. Laminar-turbulent transition induced by free-stream turbulence is of great interest due to its occurrence in many practical situations. Keeping the flow laminar can reduce drag, which results in lower fuel consumption and lower carbon dioxide emissions, contributing to an environmentally sustainable air transport system. The primary goal of the proposed project is to study the effects of the free-stream turbulence characteristic length scales and intensity on the transition in an incompressible flat-plate boundary layer. The numerical setup corresponds to the experimental investigations by Shahinfar & Fransson (2013). This requires capabilities to accurately and concurrently simulate various physical phenomena of flow, such as laminar-turbulent transition, tracking of turbulent spots and turbulent boundary layer on the wall surface. Direct numerical simulation (DNS) methods can resolve all the essential scales down to the smallest turbulent features. DNS also provides a wealth of new information, such as access to complete velocity fields, their sensitivity to important parameters and access to flow regimes not possible in physical experiments. Free-stream turbulence of higher intensity levels and its effect on boundary layer transition is complicated and still poorly understood. There exist numerous empirical relationships between the location of transition onset and the turbulence intensities in a boundary layer, but more recent investigations have shown that the turbulence intensity level is not the only dependent variable. It has been shown by Shahinfar & Fransson (2013) that the length scales have a week but the peculiar effect on the transition location. The present study aims to perform a numerical simulation of transition in a boundary layer subject to free-stream turbulence. As a summary the goals, we will: We want to: * study the effects of the free-stream turbulence characteristic length scales and intensity on the transition in an incompressible flat-plate boundary layer using direct numerical simulation (DNS). With this research, we aim to understand and explain the experimental observations by Shahinfar & Fransson (2013) numerically and to contribute to the extension of fundamental knowledge of the specifics of bypass transition. * identify the effect of the leading edge on the boundary-layer receptivity to impinging free-stream turbulence. With calculating the receptivity coefficient and quantifying the scales that enter in the boundary layer, we can find a correlation between FST scales and transition mechanism. use our data to improve cellular automaton representation model for a laminar-turbulent transition. Especially the nucleation model, for which the local conditions (turbulence intensity, length scales etc.) are taken into account. Our data can then serve as a basis for a new data-driven version of the nucleation model. * create an open database of the flow case to be used by other researchers calibrating transition models and novel eduction methods.

Project Title: TRUFLOW

Project Leader: Dr. Stéphane Zaleski, Sorbonne Universite, France

Multi-year Proposal: Year 1

Resource Awarded

• 50 000 000 core hours on Joliot-Curie Rome hosted by GENCI at CEA, France

Research Field: Engineering

Collaborators

• Sagar Pal, Sorbonne Universite, France
• Stephane Popinet, Sorbonne Universite, France
• Cesar Pairetti, Sorbonne Universite, France
• Nelson Joubert, Sorbonne Universite, France
• Jacob Maarek, Sorbonne Universite, France

Abstract

The prediction of heat and mass transfer across fluctuating fluid interfaces is a considerable challenge. It is however not only a ubiquitous part of industrial processes, but also a critical component of the global climate system through ocean-atmosphere interactions. Sustainable development and greenhouse gas emission containment will require an overhaul of already knowledge-intensive processes. TRUFLOW thus aims at enabling the quantitative prediction of the heat and mass transfer in fluid flow using simulation, high performance computation and multiphysics, multiscale methods. Using presently available, cutting edge interface tracking and subgrid scale methods TRUFLOW will investigate a range of critical processes, allowing industry to plan for new processes such as hydrogen-based metallurgy, heat and mass transfer, boiling and cavitation simulation and CO2 transfer across the wavy ocean surface. The key limiting factor in the success of simulation in this domain is the considerable range of scales expected, with slowly diffusing chemicals creating boundary layers that are orders of magnitude smaller than the typical fluid structures, bubbles or droplets. TRUFLOW will result in direct high performance simulations of heat and mass transfer and a systematic use of these models in industrial or natural configurations. We describe a five year research plan.

Project Title: REVOLUTION – masteRing thE deVelopment of the spinning cOmbustion technoLogy to redUce polluTants emIssions of aerOnautical eNgines

Project Leader: Dr. Stéphane Richard, Safran Helicopter Engines, France

Resource Awarded

• 35 000 000 core hours on Joliot-Curie (SKL) hosted by GENCI at CEA, France

Research Field: Engineering

Collaborators

• Pasquale Walter Agostinelli, Safran Helicopter Engines, France
• Laurent Gicquel, CERFACS, France
• Bénédicte Cuenot, CERFACS, France
• Gorka Exilard, Safran Helicopter Engines, France
• David Barré, GDTech, France
• Gabriel Staffelbach, CERFACS, France
• Bastien Rochette, CERFACS, France

Abstract

Global warming, climate change and pollution are burning environmental issues. To reduce the carbon footprint of the aviation sector, aeronautical companies have been striving to lower engine emissions via the development of reliable lean combustors. To do so, effort has been devoted to a better understanding of the various flame dynamics observed in such burners with emphases on thermoacoustic instabilities, lean blow-off and extinctions. In line with this effort, Safran Helicopter Engines has recently developed and patented the revolutionary spinning combustion technology (SCT) which is to be used in its next generation of combustors. This technology has indeed showed great flexibility when it comes to ignition and blow-off capabilities. It has furthermore been observed to be quite robust to thermoacoustic instabilities. However, the various physical mechanisms at play in a SCT combustor, such as strong flame-flame and flame-wall interactions, are yet not fully understood and a joint numerical and experimental analysis is here devised to fill this gap of knowledge. The objectives are to further deploy this technology for the helicopter and aircraft markets. On the experimental side, the Norwegian University of Science and Technology (NTNU) atmospheric annular combustor has been modified to introduce a relevant azimuthal component of velocity and the CORIA HERON test bench has been equipped with a SCT liquid injector. On the numerical side, high fidelity Large Eddy Simulations (LES) of the two test benches, providing insights on the flame dynamics in this unique SCT geometry are envisioned but requires HPC resources for reliable predictions. Such simulation tools will indeed allow improving the development of the spinning combustion technology which setting-up very efficient and eco-friendly combustors.

Project Title: LEISURE – Large-scalE numerical sImulation of SUpersonic turbulent boundary layers with surface RoughnEss

Project Leader: Prof. Matteo Bernardini, Sapienza University of Rome, Italy

Resource Awarded

• 38 700 000 core hours on Marconi100 hosted by CINECA, Italy

Research Field: Engineering

Collaborators

• Srikanth Chowdadenahalli Sathyanarayana, University of Rome La Sapienza, Italy

Abstract

The LEISURE project aims at studying the effects of surface roughness on the mean and turbulent properties of high-Reynolds-number supersonic turbulent boundary layers. High speed aircrafts travelling at supersonic speeds are vulnerable to the outset of surface roughness, usually associated to the increase of skin friction drag and convective heat transfer. Studying these flows is critical in several aerospace applications. The majority of research to predict and understand these flows have been limited to experiments. These experiments have laid the foundation into providing a fundamental understanding of the physics of supersonic boundary layers with surface roughness. However, the database is not very comprehensive and little is known about the effects of different roughness geometries along with varying Mach and Reynolds numbers. LEISURE proposes to tackle these problems and bridge the gaps currently present in understanding these flows through a numerical characterization. This is done through large scale Direct Numerical Simulations (DNS) which was historically improbable to be performed for such high Reynolds number flows. This enormous task will be addressed through the usage of the powerful GPU technology. Surface roughness is currently an inevitable problem due to the presence of inherent roughness through manufacturing defects. These simulations will therefore give us a deeper understanding on the working of supersonic boundary layers which will certainly help build efficient future high-speed vehicles.

Project Title: FANTASTIC-H2 – FlAme-turbuleNce inTerActions and inStabiliTIes in CH4/H2 combustion

Project Leader: Dr. Davide Laera, CERFACS, France

Resource Awarded

• 25 000 000 core hours on Joliot-Curie Rome hosted by GENCI at CEA, France

Research Field: Engineering

Collaborators

• Eleonore Riber, CERFACS, France
• Pasquale Walter Agostinelli, CERFACS, France
• Thomas Jaravel, CERFACS, France
• Gabriel Staffelbach, CERFACS, France

Abstract

This project is focused on the fundamental problem of hydrogen enriched combustion that has many practical implications in land-based gas turbines and aero-engines. Indeed, the combination of hydrogen with standard carbon-based fuels is nowadays considered as one of the most promising technical solution for clean combustion. Nevertheless, aside from these positive aspects, bi-fuel combustion rises multiple questions in terms of understanding the combustion performances (turbulent flame structure and instabilities) and safety. In this context, high-fidelity Large Eddy Simulation (LES) represents a fundamental tool to fill this gap of knowledge. The objective of the present project is to perform LES of atmospheric and high pressure swirled hydrogen/methane air flames. Numerical results will be compared with experiments carried out at DLR Stuttgart in the unique PRECCINSTA HIPOT facility where multiple CH4/H2 blends have been tested at various pressures. First, turbulent combustion of the complex flame structure of methane/hydrogen flames will be investigated. Modelling of bi-fuel chemical kinetics, complex transport properties and turbulence/combustion interactions will be focused on. The second part will deal with combustion dynamics: LES results will be analysed to fully understand the impact of hydrogen injection on the mechanisms responsible for the resonant coupling leading to thermoacoustic combustion instability.

Project Title: SEPREA – high-order accurate direct numerical simulations of SEParating and REAttaching flow

Project Leader: Dr. Andrea Cimarelli, University of Modena and Reggio Emilia, Italy

Resource Awarded

• 40 000 000 core hours on Joliot-Curie (KNL) hosted by GENCI at CEA, France

Research Field: Engineering

Collaborators

• Enrico Stalio, University of Modena and Reggio Emilia, Italy
• Roberto Corsini, University of Modena and Reggio Emilia, Italy
• Diego Angeli, University of Modena and Reggio Emilia, Italy

Abstract

The understanding of separating and reattaching flows is known to be of overwhelming interest for several applications. The main feature of these flows is the combined presence of small scales, owing to the occurrence of turbulence, and very large scales, owing to the presence of vortex shedding. The understanding of these interacting phenomena would be of paramount importance for the prediction and control of relevant issues such as wind loads and heat transfer on buildings. Archetypal of these phenomena is the flow around a finite rectangular plate. However, owing to the high sensitivity of the flow on the boundary conditions in experiments and on the turbulence model and numerical schemes in simulations, a large variability of results is found in the literature. In the present project we address this issue by performing high-order accurate Direct Numerical Simulations to provide reliable data for a correct understanding and modelling of the problem. By solving a passive scalar equation, these simulations will enable also a rigorous assessment of the heat transfer mechanisms which is relevant for a plethora of applications.

Project Title: INTAkE–understandINg Turbulence over porous surfaces: towards efficient Acoustic linErs for aircraft engines

Project Leader: Dr. Davide Modesti, Delft University of Technology, Netherlands

Resource Awarded

• 50 000 000 core hours on Piz Daint hosted by CSCS, Switzerland

Research Field: Engineering

Collaborators

• Stefan Hickel, Delft University of Technology, Netherlands
• Haris Shahzad, Delft University of Technology, Netherlands
• Luis Laguarda Sanchez, Delft University of Technology, Netherlands
• Jordi Casacuberta Puig, Delft University of Technology, Netherlands

Abstract

The aim of INTAkE project is to understand the flow physics of acoustic liners, a particular kind of porous surfaces used to attenuate the noise of aircraft engines. Acoustic liners are based on the idea of Helmholtz resonator, namely a wall cavity able to attenuate specific noise frequencies. Although the physics of a single Helmholtz resonator is well understood, little is know about turbulent flows over porous walls, with the result that the design of acoustic liners is often left to trial and error. Even though acoustic liners represent the state-of-the-art technology for engine-noise reduction, they have the major drawback of increasing the total aerodynamic drag, therefore increasing fuel consumption and emissions. During the INTAkE project we will carry out unprecedented large scale direct numerical simulations of the flow over realistic liner geometries. This challenging task will be tackled using the GPU technology and results will represent a substantial advancement to the current state of the art. The simulations will be the first of their kind and will allow us to reach a deeper understanding of the flow mechanisms occurring over porous walls and help us to design more efficient noise attenuation surfaces with limited aerodynamic drag penalty.

Project Title: SRS-T2C: Scale Resolved Studies on Turbulence in Transonic Compressor flows

Project Leader: Dr. Christoph Bode, University of Braunschweig, Germany

Resource Awarded

• 5 400 000 core hours on JUWELS Booster hosted by GCS at FZJ, Germany
• HLST Support

Research Field: Engineering

Collaborators

• Richard Sandberg, University of Melbourne, Australia
• Jake Leggett, University of Melbourne, Australia
• Pawel Przytarski, University of Melbourne, Australia
• Jens Friedrichs, University of Braunschweig, Germany

Abstract

As part of the global megatrend “Mobility”, aviation has grown exponentially by about 5% annually over the last six decades and is predicted to double every 15 years over the next decades. Despite the efforts made so far to improve jet engine efficiency, air transport still has an enormous impact on climate change and is therefore of high societal significance. The project will help to mitigate the negative effects of the drastically increasing environmental pollution associated with this growth and contribute to the achievement of EC’s “Flightpath 2050” targets. A major scientific and technological contribution is seen in the increase of efficiency and reliability of future jet engines and their components such as the compressor by further development of the computer-based methods used in the industrial design process. The further development of these tools requires high-resolution validation data, which can only be generated in an experimental environment with a high expenditure of resources. With the help of high performance computing scale-resolving simulations are a suitable means of generating this validation data giving important physical insight into the complex 3D flow in a turbo compressor that challenge future design of high pressure compressors and enables improving design tools. The study will focus on a transonic compressor stage typical for a front stage of a high pressure compressor within an aero-engine. This gas flow can only be simulated accurately with large computing power because the gas flow is turbulent and affected by interactions between moving and stationary components which creates a highly unsteady flow. Scale resolving simulations are necessary to determine the effects of turbulence and flow unsteadiness on the aerodynamics, which affects the efficiency of the aero-engine. However, experimental measurements have to date not been able to provide data with enough depth to identify all fundamental mechanisms and to explain weakness of currently used design tools due to performing engine-scale experiments and acquiring spatially and temporally resolved data. For this high Mach and Reynolds number flows wall resolved Large Eddy Simulation constitutes the only tool for investigating a transonic compressor stage in detail for developing an improved understanding of the role of turbulent phenomena on the flow-field, and for determining the validity of current turbulence modeling. For this project, we will use highly efficient software which is suitable for large parallelized computations. In addition to developing a broader insight into fundamental fluid dynamic questions related to shockwave boundary layer and wake blade interactions, the results will also provide a valuable benchmark that can be used to validate and improve current and future modeling of turbulence. The accuracy of such turbulence models is crucial to the development of high performance aero-engines and its components.

Project Title: EPPS – High-Fidelity Plasma Simulation of Electric Propulsion Systems

Project Leader: Dr.Ing. Stephen Copplestone, boltzplatz – Numerical Plasma Dynamics, Germany

Resource Awarded

• 35 000 000 core hours on Hawk hosted by GCS at HLRS, Germany

Research Field: Engineering

Collaborators

• Marcel Pfeiffer, University of Stuttgart, Germany
• Paul Nizenkov, boltzplatz – Numerical Plasma Dynamics, Germany
• Asim Mirza, boltzplatz – Numerical Plasma Dynamics, Germany

Abstract

Electric propulsion systems are highly important for current and future space programs that are being developed worldwide. The current trend towards satellite mega-constellations requires fuel-efficient propulsion systems such as electric plasma thrusters. The extreme environmental conditions that are encountered in space vacuum pose heavy demands regarding costly experimental research projects. Besides experimental investigations, numerical simulations have gained tremendous importance in developing new concepts for electric propulsion systems, e.g., Hall-effect thrusters (HET) or high-efficiency multi-stage plasma (HEMP) thrusters, in order to gain significant insight into the highly complex physical phenomena. This can be accomplished via particle-based simulation tools that consider the fully kinetic nature of the problem. These, however, require an increased computational demand as compared with conventional field-based solvers and various large-scale applications are still infeasible to examine via numerical simulation today. The 3D multi-scale plasma flow simulations performed in this project will be conducted using the open-source simulation tool PICLas, which has been developed cooperatively by the Institute of Space systems and the Institute of Aerodynamics and Gas Dynamics at the University of Stuttgart and their spin-off boltzplatz. PICLas offers parallel, three-dimensional Particle-In-Cell (PIC) coupled with Monte Carlo Collision (MCC) or Direct Simulation Monte Carlo (DSMC) simulations and is fully MPI-parallelized by domain-decomposition via space-filling curves and has been optimized for high-performance computing systems over the past years. The solver considers dynamic workload balancing by sampling the specific workload of important program subroutines during the simulation, which is necessary when increasing the number of processors, especially during highly complex and heterogeneous simulation set-ups as are considered in this proposal. Current word count: 261

Project Title: WIMPY – Wind Turbines Multi Physics

Project Leader: Dr. Bastien Duboc, Siemens Gamesa Renewable Energy, France

Resource Awarded

• 24 800 000 core hours on Joliot-Curie Rome hosted by GENCI at CEA, France

Research Field: Engineering

Collaborators

• Pierre Bénard, CORIA / INSA Rouen, France
• Félix Houtin Mongrolle, CORIA, France
• Laurent Bricteux, University of Mons, UMONS, Belgium
• Stéphanie Zeoli, University of Mons, UMONS, Belgium
• Ghislain Lartigue, CORIA, France
• Vincent Moureau, CORIA, France

Abstract

With the increasing size of offshore wind turbines, multiphysics effects like fluid-structure interactions have become critical for their performances. Indeed, blade deformation can reach more than 10 meters at the tip causing fatigue that may reduce the rotor lifetime. The project WIMPY aims at bringing new understanding on the flow around large wind turbines via high-fidelity Large-Eddy Simulations (LES). The low Mach-number flow solver YALES2, which is a recognized high-performance CFD platform, is here coupled with the aero-servo-elastic code BHawC, a well-validated engineering tool, to consider structural deformations and turbine control systems. The strategy will be applied to academic and industrial rotors with different wind speeds, yaw angles or turbulence levels. The final target is to model the Horns Rev 2 wind farm containing 91 turbines. Results will be analyzed and compared to actual wind farm data and to lower order wake models. This WIMPY project objectives aims a real scale-up compared to state-of-the art computations. The results will be published to serve as a reference database for the wind turbine modeling community.

Project Title: Partially Premixed Turbulent Combustion of Alternative Fuels in Large Marine Engines

Project Leader: Prof. Jens Honore Walther, Technical University of Denmark, Denmark

Resource Awarded

• 37 700 000 core hours on Joliot-Curie Rome hosted by GENCI at CEA, France

Research Field: Engineering

Collaborators

• Xue-Song Bai, Lund University, Sweden
• Jiun Cai Ong, Technical University of Denmark, Denmark
• Arash Nemati, Technical University of Denmark, Denmark
• Min Zhang, Technical University of Denmark, Denmark
• Kar Mun Pang, MAN Energy Solutions, Denmark

Abstract

Large two-stroke marine diesel engines are the dominant propulsion system for the international shipping industry. To comply with stringent regulations on greenhouse gas emissions, the marine industry is currently considering alternative fuels. The goal of the present research project is to understand the combustion phenomena of partially premixed alternative fuel in a large marine engine. Key focus is placed on the interplay between the complex turbulent flow in the engine and the combustion processes of dual-fuels, as well as their effects on the emission formation. All these will lead to a better understanding of the operation of large marine engines with alternative fuels. We plan to run diesel and dual-fuel spray combustion simulations in a high pressure, constant volume chamber. This numerical study allows an in-depth analysis of the spray combustion phenomenon in a controlled environment. In addition, a comprehensive full engine simulation from the scavenging process to the combustion stage in a two-stroke, large marine engine will be performed to evaluate the performance of dual-fuel combustion in a full size marine engine.

Project Title: STRIKE – Shock Transition Regime In rocKet Engine

Project Leader: Dr Guillaume Daviller, Centre Européen de Recherche et Formation Avancée en Calcul Scientifique, France

Resource Awarded

• 35 600 000 core hours on Joliot-Curie (KNL) hosted by GENCI at CEA, France

Research Field: Engineering

Collaborators

• Gabriel Staffelbach, CERFACS, France

Abstract

Improving the propulsive performance of rocket engines is a major challenge in a highly competitive context that aims at putting satellites into orbit at a lower cost. The prevailing limiting feature from producing relevant and fast solutions is the nozzle jet flow separation. This mechanism is an aerodynamic phenomenon occurring in the critical phases of ignition and extinction. It is characterized by the propagation of a non-axisymmetric separation line along the wall of the nozzle which induces significant side-loads to the structure. This problem has had significant impact on the design and production of rocket engine nozzles. The development of predictive methods for such instabilities is then of great importance for the industry. The main objective of this work is to perform for the first time a Large Eddy Simulations of a nozzle fluid dynamics during start and shutdown. The transition between the Free Shock Separation regime and the Restricted shock Separation regime that occur increasing the nozzle pressure ratio is of particular interest in order to identify and understand the mechanisms leading to instability as well as to help the development of reduced-order models. The last objective of this work is then to assess the ability of high fidelity calculations to predict such instabilities in realistic configurations and to propose a suitable and reproducible methodology. The high flow regime and physical complexity of representative rocket engines requires the use of high performance computing (HPC).

Project Title: Simulation and modelization of air pressurized flow in high temperature solar receiver

Resource Awarded

• 7 000 000 core hours on Joliot-Curie (SKL) hosted by GENCI at CEA, France

Research Field: Engineering

Collaborators

• Martin David, PROMES-CNRS, France

Abstract

Concentrated solar power plant uses the concentrated solar radiation to heat a fluid. The solar receiver is very important because it transfers the heat toward the fluid. We limit the framework of our study to pressurized air systems. Temperature has an active role on the flow (thermal expansion). Our goal is to analyze and understand fluid behavior in solar modules. In particular, we take into account the coupling effect between temperature and turbulence solving Navier-Stokes equations under the low Mach number approximation. The flow comprehension will be useful for solar receiver optimization. Indeed, to ensure the technology competitiveness it is necessary to maximize heat transfers while minimizing pressure losses. For this purpose, we plan to perform flow simulations in the module for different temperature ranges. Our working conditions are representative of the THEMIS solar power plant experimental situation. The Reynolds number is around 100 000, and heat transfers between wall and fluid reach 280 kW/m². We modelize the solar receiver with a bi-periodic channel flow made of fixed wall temperatures.

## Fundamental Constituents of Matter

Project Title: NPiTwist – The Nπ system using twisted mass fermions at the physical point

Project Leader: Prof. Constantia Alexandrou, University of Cyprus, Cyprus

Multi-year Proposal: Year 2

Resource Awarded

• 38 500 000 core hours on Hawk hosted by GCS at HLRS, Germany
• 51000000 core hours on Piz Daint hosted by CSCS, Switzerland

Research Field: Fundamental Constituents of Matter

Collaborators

• Karl Jansen, DESY, Germany
• Marcus Petschlies, University of Bonn, Germany
• Carsten Urbach, University of Bonn, Germany
• Giannis Koutsou, The Cyprus Institute, Cyprus
• Kyriakos Hadjiyiannakou, The Cyprus Institute, Cyprus
• Jacob Finkenrath, The Cyprus Institute, Cyprus
• Davide Nole, The Cyprus Institute, Cyprus
• Simone Bacchio, University of Cyprus, Cyprus
• Floriano Manigrasso, University of Cyprus, Cyprus
• Antonino Todaro, University of Cyprus, Cyprus
• Bartosz Kostrzewa, University of Bonn, Germany
• Roberto Frezzotti, Universita di Roma Tor Vergata, Italy

Abstract

In parallel to the high-energy experiments performed at CERN searching for Beyond the Standard Model (BSM) physics, low-energy high-intensity experiments, such as those at Jefferson Laboratory, FermiLab, and MAMI in Mainz, are providing complementary precision results that may prove equally insightful in detecting new physics. Examples belonging to the latter class are experiments on the proton charge radius and the muon g-2, which revealed puzzling discrepancies that could hint for BSM physics. For this precision frontier of particle physics, a major challenge is to determine accurately the contributions due to the strong interaction component of the Standard Model, governed by the theory of Quantum Chromodynamics (QCD). Being non-perturbative over the energies of interest, these contributions can only be accessed from first principles via large scale simulations of the theory. The goal of this three-year project is to study the nucleon sector, its resonances, and scattering processes from first principles using lattice QCD. A two-fold program is proposed, for new simulations on large volumes with physical light, strange, and charm quarks, employing the CPU system HAWK, and for their analysis using the GPUs of Piz Daint, to study nucleon structure, the Δ-resonance, and N-π scattering. Key observables that will be computed are nucleon form-factors, the Δ-width, and N-π scattering lengths. The calculation of N-π scattering lengths from the lattice is especially timely, since it addresses the tension between the value extracted from phenomenology and that inferred from lattice QCD computations of the nucleon σ-term, impacting searches for dark matter candidates. Our simulation will generate one of few ensembles world-wide at the physical point with box length over 7 fm. Beyond the hadron structure program foreseen within this project, this large volume will enable a series of high-impact projects of the Extended Twisted Mass Collaboration for its multi-year physics program, which includes flavor physics, semi-leptonic decays, nucleon structure including the neutron electric dipole moment, muon g-2, and direct evaluation of parton distribution functions.

Project Title: Acceleration control and superradiance in laser-plasma accelerators

Project Leader: Dr. Jorge Vieira, Instituto Superior Tecnico, Portugal

Resource Awarded

• 32 000 000 core hours on MareNostrum 4 hosted by BSC, Spain

Research Field: Fundamental Constituents of Matter

Collaborators

• Elisabetta Boella, Lancaster University, United Kingdom
• Mariana Moreira, Instituto Superior Técnico, Portugal
• Camilla Willim, Instituto Superior Técnico, Portugal
• Ricardo Fonseca, Instituto Superior Técnico, Portugal
• Anton Helm, Instituto Superior Técnico, Portugal
• Thales Silva, Instituto Superior Técnico, Portugal
• Miguel Pardal, Instituto Superior Técnico, Portugal
• Bernardo Malaca, Instituto Superior Técnico, Portugal

Abstract

Particle accelerators and light sources are pillars of modern science. A radically new concept relying on the incredibly high accelerating fields in plasmas could hold the key towards miniaturized accelerators and light sources, with broad scientific, technological and societal implications. Plasma accelerators demonstrate great promise but a key challenge remains: how to deliver the required beams for the applications. In our project we explore some of the unknown and exciting new phenomena associated with advanced spatiotemporal couplings in light and particle beams in connection with the most recent advances joining optics, photon science, and plasma physics in order to address these challenges, in order to provide more efficient and compact particle accelerators and light sources.

Project Title: ALSO – ion Acceleration from Laser-Shaped Overcritical gas jets

Project Leader: Mr. Julien Bonvalet, Centre Lasers Intenses et Applications (CELIA), France

Resource Awarded

• 60 000 000 core hours on Joliot-Curie Rome hosted by GENCI at CEA, France

Research Field: Fundamental Constituents of Matter

Collaborators

• Philippe NICOLAI, Centre Lasers Intenses et Applications – Université de BORDEAUX, France
• Jean-Raphaël MARQUES, Laboratoire pour l’Utilisation des Lasers Intenses LULI, France
• Emmanuel d’Humières, Centre Lasers Intenses et Applications – Université de BORDEAUX, France
• João Jorge Santos, Centre Lasers Intenses et Applications – Université de BORDEAUX, France
• Vladimir Tikhonchuk, Centre Lasers Intenses et Applications – Université e BORDEAUX, France
• Jocelyn DOMANGE, Centre Etudes Nucléaires de Bordeaux Gradignan – CNRS, France
• Medhi TARISIEN, Centre Etudes Nucléaires de Bordeaux Gradignan – CNRS, France
• Fazzia HANNACHI, Centre Etudes Nucléaires de Bordeaux Gradignan – CNRS, France
• Pascal LOISEAU, CEA, France
• Livia LANCIA, Laboratoire pour l’Utilisation des Lasers Intenses LULI, France

Abstract

Laser-driven ion acceleration is an attractive way to realize compact and affordable ion sources for many exciting applications including cancer therapy, proton radiography, and inertial confinement fusion. The potential developments depend on the ability of laser facilities to deliver well monitored and reproducible ion beams at high repetition rates. In this context, the use of a gas jet target is a promising way. When a near critical target is irradiated by a laser pulse, under certain conditions, an electrostatic shock can be launched in the target. These shocks can reflect upstream ions and yield ion beams with monoenergetic peaks of few MeV. Actually, the ion energy is very limited by losses of laser energy due to non-linear phenomena (self channelling and filamentation) that occur in the density ramp of the gas jet. We have already demonstrated numerically the possibility to accelerate ions to higher energies (several tens of MeV) by optimizing the gas jet profile. To achieve this goal, one or two nanosecond laser beams propagating perpendicularly to the main ps laser pulse, in the low density edge of the density profile are used to shape the gas profile. Some 2D PIC simulations have already been performed to design the next experiments. But as 2D simulations cannot quantitatively reproduce the experimental measurements, accurate design of the experimental setup requires to simulate the interaction between laser and gas jet in 3D and cylindrical geometries. With the help of these CPU hours, we will explore and design interaction parameters where optical shaping allows to increase the ions energies reached by the Collisionless Shock Acceleration mecha-nism. Several parameters have to be explored: initial gas density before shaping, timing of the main ps laser irradiation, laser duration and intensity. The numerical code SMILEI will be used in this project. Morever, this project will present the unique opportunity to benchmark our numerical code thanks to the experimental measurements. The experimental campaigns, already planned to be realized at the end of 2020 or beginning of 2021 (depending on the coronavirus deconfinement), will provide us sev-eral diagnostics related to the laser accelerated beams, strongly useful to improve our numerical models. By accessing to a large amount of CPU hours, we will be able to associate experimental measurements with numerical experiments in order to produce high energy laser-accelerated ion beams using gas jets.

Project Title: Coding the cosmos: From cosmic strings to superstrings

Project Leader: Dr. Carlos Martins, Centro de Astrofísica da Universidade do Porto, Portugal

Resource Awarded

• 68 000 000 core hours on Piz Daint hosted by CSCS, Switzerland

Research Field: Fundamental Constituents of Matter

Collaborators

• José Ricardo Correia, Centro de Astrofísica da Universidade do Porto, Portugal

Abstract

Cosmic strings are the best-known example of topological defects: fossil remnants of earlier phases of the Universe which may survive up to the present day, encoding crucial information of fundamental physics regimes that would otherwise be inaccessible. Searching for therir observational imprints is a key goal of forthcoming observational facilities, including LISA, COrE and the SKA. Being non-linear objects, the study of their dynamcs, evolution and consequences heavilty relies on HPC, complemented by analytic phenomenological modelling. Current observational searches are bottlenecked by the lack of numerical simulations with sufficient spatial resolution and dynamical range to calibrate existing analytic models. A successful previous proposal (2019204986) allowed us to use a large set of high-resolution large dynamic range Piz Daint simulations to calibrate and improve analytic models for the simplest case of Abelian-Higgs strings. The present proposal goes beyond the previous one in two different ways: (i) for Abelian-Higgs strings, we wil do additional high spatial resolution simulations optimized to characterize the string properties on small sub-horizon scales, with the goal of characterizing their fractal properties and energy losses from loop production and scalar and gauge radiation; (ii) we will use a new extended version of the code (already bechmarked at Piz Daint) to perform a pioneering numerical study of networks of interconnected field theory strings (that are proxies for cosmic superstring networks) and thereby calibrate recently proposed analytic models for them. Together, these will enable significantly more robust observational predictions to be made for all these networks, helping forthcoming astrophysical searches and improving constraints on the underlying physics.

Project Title: High precision strong coupling

Project Leader: Prof. Dr. Rainer Sommer, DESY, Germany

Resource Awarded

• 10 000 0000 core hours on Hawk hosted by GCS at HLRS, Germany

Research Field: Fundamental Constituents of Matter

Collaborators

• Francesco Knechtli, University of Wuppertal, Germany
• Roman Höllwieser, University of Wuppertal, Germany
• Tomasz Korzec, University of Wuppertal, Germany
• Mattia Dalla Brida, University Milano-Bicocca, Italy
• Stefan Sint, Trinity College, Ireland
• Alberto Ramos, Trinity College, Ireland

Abstract

Quantum Chromodynamics (QCD) is the theory of the strong interactions among the elementary particles called quarks and gluons, which are the building blocks of hadrons such as the proton and the neutron. Through the formulation of QCD on a Euclidean lattice the theory becomes amenable to computer simulations and it is possible to compute hadron properties from first principles. The running coupling strength $\alpha_s$ can also be computed from lattice QCD. A precise knowledge of this fundamental parameter of the Standard Model (SM) of elementary particles is an honorable goal in itself, but it is also crucial for the search of new physics as discrepancies between the Standard Model’s predictions and experiments at colliders like the LHC are already restricted to be small. With a new method we will improve the precision of our previous determination of $\alpha_s$ by a factor of two and bring down the error of the world average accordingly.

Project Title: PiGG – Neutral pion coupling to photons from lattice QCD at physical quark masses

Project Leader: Prof. Harvey Meyer, Johannes Gutenberg-Universitaet Mainz, Germany

Resource Awarded

• 57 100 000 core hours on Hawk hosted by GCS at HLRS, Germany

Research Field: Fundamental Constituents of Matter

Collaborators

• Antoine Gerardin, University of Aix-Marseille, France
• Konstantin Ottnad, Johannes Gutenberg-Universitaet Mainz, Germany
• Daniel Mohler, Johannes Gutenberg-Universitaet Mainz, Germany

Abstract

The goal of our proposal is to perform precision tests of the Standard Model of particle physics. The idea is confront an experimentally measured property of a particle to its theory prediction. In this project we will compare the experimentally measured neutral pion lifetime to our prediction from first-principles simulations. We will also compute the neutral pion contribution to another precision obervable, the anomalous magnetic moment of the muon, which has been measured extremely accurately. We use a theory framework called lattice QCD. A realistic simulation in that framework requires major high-performance computing resources to handle the large system size, a 96x96x96x192 lattice. When combining this calculation with our previous calculations, we expect to obtain predictions of unique quality.

Project Title: EMGKPIC – Gyrokinetic PIC simulations of electromagnetic turbulence in tokamaks and stellarators

Project Leader: Dr. Oleksiy Mishchenko, Max Planck Institute for Plasma Physics, Germany

Resource Awarded

• 200 000 000 core hours on Marconi100 hosted by CINECA, Italy
• 30 000 000 core hours on Joliot-Curie (SKL) hosted by GENCI at CEA, France

Research Field: Fundamental Constituents of Matter

Collaborators

• Thomas Hayward-Schneider, Max Planck Institute for Plasma Physics, Germany
• Ralf Kleiber, Max Planck Institute for Plasma Physics, Germany
• Alessandro Biancalani, Max Planck Institute for Plasma Physics, Germany
• Alberto Bottino, Max Planck Institute for Plasma Physics, Germany
• Axel Koenies, Max Planck Institute for Plasma Physics, Germany
• Laurent Villard, Swiss Plasma Center, Switzerland
• Michael Cole, Princeton Plasma Physics Laboratory, United States

Abstract

With the reserve of fossil fuels running out and the world’s increasing energy demands, it is mandatory to develop alternative energy sources. Controlled fusion is one of such sources with the potential to provide a virtually inexhaustible energy supply, safer than fission and free of producing greenhouse gasses. The development of large machines like tokamak ITER and stellarator W7-X is a necessary step towards achieving this goal. The fusion performance of such machines relies on our understanding of plasma confinement which can be strongly affected by the turbulent transport. Global gyrokinetic particle-in-cell (PIC) codes provide an excellent framework for the full-device long-time cross-scale modelling of fusion plasmas in general magnetic geometry (both tokamaks and stellarators). The cross-scale aspect of the modelling addresses micro-turbulence co-existing with the large-scale MHD-like disturbances and radial profile evolution (related for example to the zonal flows) and in presence of the energetic particles. These aspects have been considered so far separately. However in reality, they are co-existing and mutually-interacting parts of a big picture, which can be described in all its complexity using the gyrokinetic PIC approach. We propose to use the ORB5 and EUTERPE codes to tackle the multiscale modelling of fusion plasmas.

Project Title: Properties of the interacting hadron gas at the QCD transition temperature

Project Leader: Dr. Christian Schmidt, Bielefeld University, Germany

Resource Awarded

• 70 000 000 core hours on Marconi100 hosted by CINECA, Italy

Research Field: Fundamental Constituents of Matter

Collaborators

• Frithjof Karsch, Bielefeld University, Germany
• Swagato Mukherjee, Brookhaven National Laboratory, United States
• Guido Nicotra, Bielefeld University, Germany
• Lorenzo Dini, Bielefeld University, Germany
• Olaf Kaczmarek, Bielefeld University, Germany
• Peter Petreczky, Brookhaven National Laboratory, United States

Abstract

The details of the QCD phase diagram at finite temperature and density are still – to a large extent – unknown. Lattice QCD calculations provide some inside to the phase boundary between the hadron gas phase and the quark gluon plasma by a leading and higher order Taylor expansion approach. Much effort is undertaken to map out this phase boundary by heavy ion experiments at the Relativistic Heavy Ion Collider (RHIC) at Brookhaven National Laboratory and the Large Hadron Collider (LHC) at CERN. A sensitive measure for the phase boundary, as well as for possible critical behavior indicating a second order phase transition point, are cumulants of conserved charges fluctuations, which are theoretically well defined. Establishing a link to the experimentally determined freeze-out temperature, which is based on measurements of particle yields (first moments) only is, however, a major challenge. We propose here to calculate a set of fourth order cumulants which are sensitive to modifications of hadron resonances and pseudo-scalar mesons due to interactions in a thermal medium, which are crucial for the experimental determination of freeze-out parameters through comparison with non-interacting hadron resonance gas models.

Project Title: HiFi-Turb-BJ – Simulation of the Bachalo-Johnson axisymmetric transonic bump at Reynolds 1 million

Project Leader: Dr. Koen Hillewaert, Université de Liège, Belgium

Resource Awarded

• 30 000 000 core hours on JUWELS hosted by GCS at FZJ, Germany

Research Field: Fundamental Constituents of Matter

Collaborators

• Michel Rasquin, Cenaero, Belgium
• Alessandro Colombo, Università degli Studi di Bergamo, Italy
• Thomas Toulorge, Cenaero, Belgium
• Francesco-Carlo Massa, Università degli Studi di Bergamo, Italy

Abstract

Design simulation in aeronautics relies on relatively cheap but low-fidelity statistically averaged turbulence models (RANS). As computational resources become more available, also scale-resolving simulations, and in particular wall modeled LES, become feasible, opening the door to new physical insights and better designs. An important stumbling block for the development of both approaches is the limited availability of high quality reference data on complex flows. Direct numerical simulations of the Bachalo-Johnson axisymmetric transonic bump are planned in this campaign, which is organized under the umbrella of the HiFi-Turb H2020 European project, focused on the development of innovative turbulence models for complex aerodynamic turbulent flows. This testcase is representative of the upper surface of transonic wing profiles and features shock-boundary layer interaction and shock-induced separation, which are critical flow regimes for wing profiles and jet engines alike. This campaign will generate an unprecedented exhaustive database in view of the development and calibration of new turbulence models using machine learning. The high-fidelity database will follow a strict protocol, defined colloquially with experts in the HiFi-Turb project, and published on the ERCOFTAC Knowledge Base Wiki. In particular through the confrontation of computational methods and rigorous budget closure checks, high quality data is targeted.

Project Title: AFIETC – Alpha-like Fast Ion Effect on Thermal Confinement

Project Leader: Dr. Jeronimo Garcia, CEA- Commission of Atomic and Alternative Energies, France

Resource Awarded

• 40 000 000 core hours on Joliot-Curie (SKL) hosted by GENCI at CEA, France

Research Field: Fundamental Constituents of Matter

Collaborators

• David Zarzoso, Aix-Marseille University, France
• Samuele Mazzi, Aix-Marseille University, France
• Yann Camenen, Aix-Marseille University, France

Abstract

Controlled thermonuclear fusion energy represents one suitable candidate to satisfy the future energy needs, providing all the characteristics of a sustainable and clean energy source. Nevertheless, the production of electricity from nuclear fusion still calls for missions to be accomplished, in particular the minimization of energy losses due to turbulent transport, mainly caused by microinstabilities. Any eventual mechanism of reduction of turbulence is highly desirable for the future exploitation of fusion devices, such as ITER. Recently, following experimental detection of increasing confinement in concomitance with highly energetic ions (fast ions), generated by plasma heating systems, dedicated analyses showed a beneficial impact of fast ions in reducing the turbulent energy fluxes and increasing, thus, the overall confinement. This project aims at the broad comprehension of the complex interaction among fast ions, microinstabilities and thermal confinement. This is done by analysing experimental plasmas with fast ion energy close to alpha-born particles from D-T reactions, which is the reaction envisaged in future tokamak reactors. With advanced numerical analyses, reactor-relevant plasma conditions will be simulated in order to deliver new understandings of the challenging fast-ion impact on thermal confinement.

Project Title: HABIL – Hard photon bursts in plasma

Project Leader: Dr. Thomas Grismayer, GoLP/IPFN – Instituto Superior Tecnico, Portugal

Resource Awarded

• 30 000 000 core hours on Joliot-Curie Rome hosted by GENCI at CEA, France

Research Field: Fundamental Constituents of Matter

Collaborators

• Luis Silva, GoLP/IPFN – Instituto Superior Tecnico, Portugal
• Bertrand Martinez, GoLP/IPFN – Instituto Superior Tecnico, Portugal
• Fábio Cruz, GoLP/IPFN – Instituto Superior Tecnico, Portugal
• Rui Torres, GoLP/IPFN – Instituto Superior Tecnico, Portugal]
• Kevin Schoeffler, GoLP/IPFN – Instituto Superior Tecnico, Portugal
• Marija Vranic, GoLP/IPFN – Instituto Superior Tecnico, Portugal

Abstract

Could the interaction of hard photons with a plasma lead to the formation of collective plasma waves? Is relativistic particle acceleration possible with the generated waves? Is there a new mechanism for coherent radio emission in those situations? These are prominent scientific questions where plasma astrophysics is intimately connected with quantum aspect of light. This proposal aims to exploit the outstanding computing facilities provided by PRACE to address these compelling challenges by leveraging the pioneered advances in coupling quantum electrodynamics effects with particle-in-cell simulations. The main scientific route to answer some of these questions consists in understanding the possible collective phenomena emerging from the interaction of x-rays and gamma-ray burst with plasmas. In particular, it is crucial to assess self-consistently the Compton scattering collision of the photons with the particles and the feedback onto the kinetic response of the plasma. This task requires a special computational effort given the separation of the scales involved, namely the macroscopic distance of propagation of the photon burst down to the microphysics of quantum scales. The first goal of this research project is to explore the complex dynamics of linear driven X-modes (Cerenkov wakes) from x-ray burst and their structure in multiple dimensions. The second goal is to to investigate what is the energy density required to generated non linear wakes close to the wave breaking limit and whether these non linear wakes resemble the ones driven by laser pulses. The third goal is to investigate in electron-ion plasma the formation of a relativistic electron beam while the gamma-ray burst propagate and to study the plasma instabilities due to the presence of the generated relativistic beam. The self-consistent study of the interdependence among the plasma dynamics pertinent to such different spatial and temporal scales is difficult and massively parallel kinetic particle-in-cell simulations are critical to establishing this bridge. The unique computational infrastructures provided by PRACE would be critical to explore some of the most exciting fundamental physics questions at the forefront of science identified in this proposal. This project will leverage on the massively parallel, fully relativistic particle-in-cell code OSIRIS, which includes a special Compton collisional module to study the interaction of high energy photon bursts with plasmas. This research route embraces the spirit and the path outlined by the ERC advanced grant in Pairs, which aims at understanding the dynamics of electron-positron pair plasmas in extreme fields. Many steps were already taken in this direction, and our numerical infrastructure is now ready to be massively employed in studying some of the most puzzling but marvelous questions in plasma astrophysics

Project Title: LatGPDs- Generalized Parton Distribution Functions from lattice simulations

Project Leader: Dr. Savvas Zafeiropoulos, CNRS, France

Resource Awarded

• 35 000 000 core hours on Marconi100 hosted by CINECA, Italy

Research Field: Fundamental Constituents of Matter

Collaborators

• Balint Joo, Jefferson Lab, United States
• Christos Kallidonis, College of William and Mary, United States
• Konstantinos Orginos, College of William and Mary, United States
• David Richards, Jefferson Lab, United States
• Joseph Karpie, Columbia University, United States
• Colin Egerer, College of William and Mary, United States
• Eloy Romero Alcalde, College of William and Mary, United States
• Robert Edwards, Jefferson Lab, United States
• Raza Sufian, Jefferson Lab, United States
• Frank Winter, Jefferson Lab, United States

Abstract

Project Title: PICT – Precision Information on Critical Theories

Project Leader: Dr. Chris Hooley, University of St Andrews, United Kingdom

Resource Awarded

• HLST Support

Research Field: Fundamental Constituents of Matter

Collaborators

• Matthew Dowens, University of St Andrews, United Kingdom

Abstract

In the nineteenth century, a profound shift took place in our understanding of physics: the discovery of fields. These fields, such as the electromagnetic field, mediated the forces between particles. Over the following decades, new fields were added to describe additional physical phenomena, including gravity and the strong and weak nuclear forces. By the mid-twentieth century the latest theoretical developments led to the description of even the particles themselves as local excitations of quantum fields. Within quantum field theory, a special place is occupied by conformal field theories. These are scale-free (or fractal) field theories, in which the nature of the fluctuations of the field is independent of the length scale on which they are observed. They describe physical systems that are at critical points: tipping points where they are just about to transition from one qualitative kind of behaviour (e.g. vapour) to another (e.g. solid). It is widely believed that the development of any system as it cools (including the universe) can be described as an evolution from one conformal field theory to another, ending up at a trivial conformal field theory in which there are no fluctuations left at all. A beautiful feature of these conformal field theories is their universality: they apply to a wide variety of physical systems whose microscopic constituents exist on very different length scales, all the way from the larger atomic nuclei, through laboratory-sized condensed matter samples, to full-scale cosmology. Despite this, they make very strong predictions for the results of experiments: in particular, they predict the critical exponents of the theory, i.e. the numbers that determine how different observable quantities grow as the critical point is approached. These critical exponents typically depend on very few features of the system – often only its spatial dimensionality and the mathematical group describing its internal symmetry – which is an illustration of the abovementioned universality. Until around ten years ago, our best method of calculating the critical exponents for a given conformal field theory, corresponding to a given universality class of critical points, was to computationally simulate the behaviour of a microscopic model that was believed to lie in that universality class. Since 2012, however, a new and powerful alternative has become available: the conformal bootstrap. This deals directly with the conformal field theory, and is thus guaranteed to have universal results; also, while still computationally intensive, it can yield precise information about the critical exponents of the theory in a fraction of the time required by more traditional methods. In this project, we propose to apply the conformal bootstrap method to conformal field theories described by direct-product groups, specifically Z_2 x O(2) and O(2) x O(2). The resulting critical exponents are relevant to unsolved problems in both high-energy theory and condensed matter physics. Our calculations will provide the most detailed predictions to date of these critical exponents, allowing comparison both with analytical theory approaches (e.g. large-N expansions) and experiment (e.g. specific heat measurements in heavy-fermion compounds and iron-based superconductors).

## Universe Sciences

Project Title: IMPACT – Retracing the formation of the Moon in the aftermath of the Giant Impact

Project Leader: Dr. Razvan Caracas, CNRS, France

Multi-year Proposal: Year 2

Resource Awarded

• 30 000 000 core hours on Joliot-Curie Rome hosted by GENCI at CEA, France

Research Field: Universe Sciences

Collaborators

• Zhi Li, CNRS, France
• Natalia Solomatova, CNRS, France
• Renata Schuler Schaan, CNRS, France
• Francois Soubiran, CNRS, France
• Anais Kobsch, CNRS, France

Abstract

We aim at characterizing the evolution of the protolunar disk generated in the aftermath of the Giant Impact from its formation until its condensation. This project was awarded an ERC Consolidator Grant, IMPACT, for the duration 2016-2021. Very little is understood of the physics governing the Giant Impact and the subsequent formation of the Moon. According to this model an impactor hit the proto-Earth; the resulting energy was enough to melt and partially vaporize the two bodies generating a large protolunar disk, from which the Earth-Moon couple formed. Hydrodynamic simulations of the impact and the disk are currently based on unconstrained models of equations of state and phase diagrams: estimates of the positions of critical points for realistic geological materials, when available at all, vary by one order of magnitude in both temperature and density. Here we use large-scale ab initio molecular dynamics to determine vaporization curves, position the supercritical points, and characterize the sub-critical and supercritical regimes for the major rock-forming minerals. We use these results to simulate the thermal profile through the disk, the ratio between liquid and vapor, and the chemical speciation. Eventually we constrain the impactor, the proto-Earth and the plausible impact scenarios.

Project Title: AIDASpace – Artificial Intelligence Data Analysis of electron-scale turbulence in the heliosphere

Project Leader: Prof. Giovanni Lapenta, K.U.Leuven, Belgium

Resource Awarded

• 40 000 000 core hours on SuperMUC hosted by GCS at LRZ, Germany

Research Field: Universe Sciences

Collaborators

• Giuseppe Arro, KU Leuven, Belgium
• Jorge Amaya, KU Leuven, Belgium
• Francesco Pucci, KU Leuven, Belgium
• Maria Elena Innocenti, KU Leuven, Belgium
• Brecht Laperre, KU Leuven, Belgium
• Joost Croonen, KU Leuven, Belgium
• Elisabetta Boella, Lancaster University, United Kingdom
• Romain Dupuis, KU Leuven, Belgium

Abstract

We will simulate the conditions observed by two recent space missions of exploration of the heliosphere. We will consider six different scenarios where the process of turbulence and the processes of magnetic reconnection interact. Reconnection converts magnetic energy into strong localised flows and into heat. The process involves density gradients, sheared flows, anisotropies and beams propagating in a plasma. These processes induce instabilities and lead to turbulence. In the turbulent outflows, reconnection can itself play another role in promoting more reconnection and energy conversion. We focus here on macroscopic systems and we test the recent discovery of reconnection at very small electron scales within turbulent regions. To reach the resolution needed we need to have large systems to fit the whole outflow region but we also need an extreme resolution to resolve electron scales. This requires the most advanced supercomputer available now. In our proposal, we request 40 million hours to conduct six types of simulations for conditions around the Earth space environment and in the solar wind at different distances from the Sun. Our simulations will produce huge datasets and we will use machine learning tools of the H2020 project AIDA to mine the necessary information.

Project Title: Particle Acceleration and Gamma-Ray Emission in the LS5039 System

Project Leader: Assoc. Prof. Dr. Ralf Kissmann, Universität Innsbruck, Austria

Resource Awarded

• 272 000 00 core hours on Joliot-Curie Rome hosted by GENCI at CEA, France

Research Field: Universe Sciences

Collaborators

• Philipp Gschwandtner, Universität Innsbruck, Austria
• David Huber, Universität Innsbruck, Austria

Abstract

Gamma-ray binaries are among the most extreme astronomical objects. They consist of a giant star and a compact stellar companion, presumably a neutron star. The majority of radiation detected from these systems is emitted at energies beyond the X-ray regime. Observation of this radiation indicates that it is produced from high-energy particles present in these systems. These particles can be accelerated in the interaction region of a highly-relativistic outflow emitted by the neutron star with the stellar wind from the giant star. Since the origin of the radiation can not be observationally resolved, understanding of the physical processes in these systems requires modelling efforts that try to recover the observations. Since these show a pronounced energy-dependence together with temporal variability, analytical models can not recover the observations due to the necessary simplifications. Modelling such a system is even challenging numerically: In a gamma-ray binary, orbital motions and (relativistic) outflows interact to produce a particle population that by a further interaction with this dynamical environment emits the observed radiation. Using HPC simulations will help improve our understanding of these objects by modelling the dynamics and the particle transport in one of these systems with unprecedented complexity.

Project Title: NRCOSMO – From the Big Bang to Black Holes and Beyond

Project Leader: Dr. Eugene Lim, King’s College London, United Kingdom

Resource Awarded

• 30 000 000 core hours on JUWELS hosted by GCS at FZJ, Germany

Research Field: Universe Sciences

Collaborators

• Katy Clough, Oxford University, United Kingdom
• Thomas Helfer, Johns Hopkins University, United States
• Miren Radia, Cambridge University, United Kingdom
• Boxuan Ge, King’s College London, United Kingdom
• Josu Aurrekoetxea, King’s College London, United Kingdom
• Francesco Muia, DESY, Germany
• Fernando Quevedo, Cambridge University, United Kingdom
• Robin Croft, Cambridge University, United Kingdom
• Pedro Ferreira, Oxford University, United Kingdom
• Ulrich Sperhake, Cambridge University, United Kingdom
• Matt Elley, King’s College London, United Kingdom
• Giuseppe Ficarra, King’s College London, United Kingdom
• Cristian Joana, University of Louvain, Belgium
• Helvi Witek, University of Illinois at Urbana-Champaign, United States
• Dina Traykova, Oxford University, United Kingdom
• Jamie Bamber, Oxford University, United Kingdom
• Eloy de Jong, King’s College London, United Kingdom
• Sebastien Clesse, University of Louvain, Belgium
• Amelia Drew, Cambridge University, United Kingdom

Abstract

The epoch defining discovery of gravitational waves (GW) in 2015 by the LIGO Observatory has opened a new window into the Universe. Long predicted by the theory of General Relativity, GW are generated in highly energetic events throughout the cosmos — in which the merger of a pair of black holes that was detected in 2015 is one such source. However, there are many other yet unexplored and little studied events – in which their discovery will allow us to directly address fundamental questions of theoretical physics that range from the cosmic origins of the Universe to the nature of the elusive Dark Matter. In this proposal, we will use advanced numerical techniques that was initially pioneered to study the merger of black holes, to answer these very questions. We will explore the viability of the paradigmatic Inflationary theory of the Big Bang, study the formation of primordial black holes from the early universe, investigate the gravitational wave signatures of Dark Matter, and search for the presence of cosmic strings predicted from our Grand Unified Theory of particle physics. Each of these projects are potentially revolutionary, making our project both important and timely.

Project Title: Unravelling the formation of the Milky Way

Project Leader: Dr. Oscar Agertz, Lund University, Sweden

Resource Awarded

• 45 000 000 core hours on Joliot-Curie Rome hosted by GENCI at CEA, France

Research Field: Universe Sciences

Collaborators

• Florent Renaud, Lund University, Sweden
• Martin Rey, Lund University, Sweden
• Eric Andersson, Lund University, Sweden
• Romain Teyssier, University of Zürich, Switzerland
• Michael Kretschmer, University of Zürich, Switzerland
• Andrew Pontzen, University College London, United Kingdom
• Justin Read, University of Surrey, United Kingdom

Abstract

Understanding how galaxies form and evolve is a grand challenge for astrophysics. The Milky Way, our home in the Universe, is one of hundreds of billions of galaxies. Being the one galaxy we can study in exquisite detail, it provides a fundamental testbed for theories of galaxy formation and evolution. Observations of stars in the disc of the Milky Way indicate the existence of several components, separated kinematically, chemically, as well as spatially. The origins of these puzzling trends have been intensely debated for decades, and the degree to which they reflect how the galaxy formed versus how it has evolved remains unsolved. Such forensic evidence will only improve as a wealth of new data is becoming available from upcoming large ground-based spectroscopic surveys, such as WEAVE and 4MOST, together with new data releases from the astrometric satellite Gaia. This data set will revolutionise the field, and holds the key to our Galaxy’s formation. However, in order to make progress towards a theory of galaxy formation, and understanding how the Milky Way formed, observational data must be deciphered using robust theoretical models. Cosmological simulations of galaxy formation, which self-consistently model the complex interaction between dark matter, gas and stars over almost 14 billion years of cosmic time since the Big Bang, are in principal ideal for this task. Such simulations offer holistic accounts of the formation of galaxies, and do not suffer from the restrictive simplifications and approximations that traditional analytical models carry. We will carry out a large suite of cosmological zoom galaxy simulations with well tested implementations of galaxy physics, from which a Milky Way candidate will be selected. We will use a new genetic modification’ technique to create a set of modified histories for this galaxy, changing fundamental aspects such as the timing and mass ratio of the last major merger. By doing so we can, in an unprecedented way, connect specific mechanisms in a galaxy’s past to its current state. Our state-of-the-art simulations will allow us to approach a ‘Virtual Milky Way’, which we will use to decipher observations of stellar populations, hence unravelling the assembly history of the Milky Way and disc galaxies in general.

Project Title: Star formation and regulation in high-redshift galaxies

Project Leader: Dr. Jérémy Fensch, Centre de Recherche Astrophysique de Lyon – ENS de Lyon, France

Resource Awarded

• 20 000 000 core hours on Joliot-Curie Rome hosted by GENCI at CEA, France

Research Field: Universe Sciences

Collaborators

• Frédéric Bournaud, CEA-Saclay, France
• Patrick Hennebelle, CEA-Saclay, France
• Noé Brucy, CEA-Saclay, France
• Karl Joakim Rosdahl, Centre de Recherche Astrophysique de Lyon, France
• Marion Farcy, Centre de Recherche Astrophysique de Lyon, France
• Taysun Kimm, Yonsei University, Korea, Republic Of
• Yohan Dubois, Institut d’astrophysique de Paris, France

Abstract

Star formation in primordial galaxies is not yet understood. Even in state-of-the-art cosmological simulations, stars do not form at the right time nor at the right place. This results from our lack of knowledge about how the physical properties of early galaxies affect how they convert their gas into stars. Early galaxies are observed to have denser and more turbulent gas and more active star formation compared to today’s galaxies. However, the interplay between relevant processes (gravity, turbulence, radiation, star formation feedback) is not yet understood: their interplay is complex and its study relies on costly numerical simulations.16   In this project, we focus on star-forming galaxies of the early Universe, at the epoch of the peak of cosmic star formation history (z~2, ~10 billion years in look-back time). By using a zoom-in method to lift a technical lock by reducing the simulations’ memory footprint, this project aims at resolving the sub-structures of the interstellar medium of these galaxies while accounting for the impact of the large-scale environment, to better understand the physical processes that regulate star-formation in primordial galaxies.

Project Title: Near-Field Cosmology with ETHOS: the interplay between baryonic physics and dark matter physics

Project Leader: Prof. Jesús Zavala Franco, University of Iceland, Iceland

Resource Awarded

• HLST Support

Research Field: Universe Sciences

Collaborators

• Sebastian Bohr, University of Iceland, Iceland
• Torsten Bringmann, University of Oslo, Norway
• Jan Burger, University of Iceland, Iceland
• Francis-Yan Cyr-Racine, The University of New Mexico, United States
• Mark Lovell, University of Iceland, Iceland
• Christoph Pfrommer, University of Potsdam, Germany
• Laura Sales, University of California Riverside, United States

Abstract

The ultimate goal of this interdisciplinary project is to test whether gravity is the only dark matter (DM) interaction that is relevant in the physics of galaxies. This is a fundamental test whose implications are far reaching across a community that is using this unproven hypothesis as the core of increasingly sophisticated models to interpret increasingly detailed observations. The PI, in collaboration with an international team working at the intersection between astrophysics, cosmology and particle physics, has been developing a theoretical framework (ETHOS) that aims at modelling how galaxies form and evolve in the broadest sense, covering a wide range of allowed DM particle physics. To reach our objectives, we need to perform HPC simulations of cosmic structure formation to study the interplay and degeneracies between gas/stellar (baryonic) physics and allowed DM physics within ETHOS. Given the potential of current (and near-future) observations in the Local Universe to answer fundamental questions about the DM nature (one of the tenets of Near-field cosmology), we propose to perform simulations of the Local Group to provide detailed predictions of the consequences of non-gravitational DM interactions for Near-field cosmology, as well as point towards unique signatures of DM physics in astronomical observations.