Latest Results Gauss Centre for Supercomputing e.V.

LATEST RESEARCH RESULTS

Find out about the latest simulation projects run on the GCS supercomputers. For a complete overview of research projects, sorted by scientific fields, please choose from the list in the right column.

Materials Sciences and Chemistry

Principal Investigator: Ulrich Aschauer, Department of Chemistry and Biochemistry, University of Bern, Switzerland

HPC Platform used: SuperMUC of LRZ

Local Project ID: pn69fu

Researchers carried out density functional theory defect calculations of materials relevant in energy applications. They calculated Raman spectra of LiCoO2 which allow to follow the structural evolution during charging and discharging of this important class of lithium-ion battery cathode materials and to understand what can lead to their failure. Furthermore, the effect of defects forming on a dissolving metastable surface on the (photo)electrocatalytic performance were calculated, and the team worked on novel computational methods applied to defects that will enable DFT calculations of defects with a similar accuracy than state-of-the-art methods, however at a much-reduced computational cost.

Life Sciences

Principal Investigator: Jacek Czub, Faculty of Chemistry, Department of Physical Chemistry, Gdansk University of Technology (Poland)

HPC Platform used: SuperMUC of LRZ

Local Project ID: pn69fe

ATP synthase is an enzyme found in organisms ranging from primitive bacteria to some of the most complex lifeforms, such as humans. Its energetic efficiency is unrivalled, but not well understood. Researchers of Gdansk University of Technology have been using HPC to study this remarkable enzyme at a level of detail never seen before.

Computational and Scientific Engineering

Principal Investigator: Timo Krappel, Institute of Fluid Mechanics and Hydraulic Machinery, University of Stuttgart

HPC Platform used: Hornet and Hazel Hen of HLRS

Local Project ID: LESFT

In recent years, hydroelectric power plants have received increased attention for the role they play in integrating volatile renewable energies that contribute to stabilizing the electrical grid. One major issue, though, is rooted in running turbines under conditions they were not originally designed for, leading to undesirable flow phenomena. With the standard modeling approaches that are typically used in industry simulations of hydroelectric turbines, simulation accuracy in scenarios where the turbine is used off-design is rather poor. The goal of this project is to increase simulation accuracy by the selection of suitable modeling approaches and the use of a fine mesh resolution, which is only possible by the use of supercomputers.

Environment and Energy

Principal Investigator: Stephan Stellmach and Ulrich Hansen, Institut für Geophysik, Westfälische Wilhelms-Universität Münster

HPC Platform used: JUQUEEN of JSC

Local Project ID: chms15

Rotating convection is ubiquitous in geophysical systems. In generates the Earth magnetic field, stirs the deep atmospheres of giant planets and possibly also drives their strong surface winds. A thorough understanding of these objects requires comprehensive insight into the physics of turbulent convective flows that are strongly constrained by Coriolis forces. Numerical simulations reveal the full three-dimensional structure of the flow, and can be used to guide theoretical modeling.

Computational and Scientific Engineering

Principal Investigator: Luis Cifuentes, Chair of Fluid Dynamics, University of Duisburg-Essen

HPC Platform used: SuperMUC of LRZ

Local Project ID: pr53fa

A GCS large-scale project under leadership of Dr.-Ing. Cifuentes of the University of Duisburg-Essen aims at understanding the physics of entrainment in turbulent premixed flames. This research characterizes the entrainment processes through the study and comparison of the flame front and the enstrophy interface. This is an essential issue in reactive turbulent flows, because a better understanding of the dynamics of the flame front and the enstrophy interface leads to better predictions of flame instabilities and scalar structures.

Materials Sciences and Chemistry

Principal Investigator: Fakher Assaad, Lehrstuhl für Theoretische Physik I, Julius-Maximilians-Universität Würzburg

HPC Platform used: SuperMUC of LRZ

Local Project ID: pr53ju

In this project, researchers use state of the art fermion quantum Monte Carlo methods to understand emergent collective phenomena in correlated electron system. The scientists define and study theoretical models where topology emerges and leads to novel particles at quantum critical points. The flexibility of their approach also makes it possible to study the physics of magnetic moments in a metallic environment. This could, for instance, enable theoretical experiments for understanding magnetic adatoms on metallic surfaces. In this report, a succinct account of the ALF (Algorithms, Lattice, Fermions) program package, which was developed by the scientists, as well as a summary of selected research projects is provided.

Life Sciences

Principal Investigator: Ville R. I. Kaila, Technical University of Munich

HPC Platform used: SuperMUC of LRZ

Local Project ID: pr84gu

In eukaryotes, conversion of foodstuff into electrochemical energy takes place in mitochondria by enzymes of the respiratory chain. Cytochrome c oxidase (CcO) reduces oxygen to water and pumps protons across the membrane. In this project, we elucidated how reduction of metal co-factors in CcO control the proton transfer dynamics. By combining atomistic MD simulations with hybrid QM/MM free energy calculations, we elucidated the location of a transient proton loading site near the active site, and identified how proton channels are activated during the different steps of the catalytic cycle.

Astrophysics

Principal Investigator: Wolfgang Hillebrandt, Max-Planck-Institut für Astrophysik, Garching b. München

HPC Platform used: JUWELS of JSC

Local Project ID: hmu14

Supernovae of Type Ia are modeled as thermonuclear explosions of a carbon-oxygen white dwarf stars. The way these trigger the explosive burning, however, is still unclear. This project performs hydrodynamic simulations that give insights into possible explosion mechanisms. With its pipeline extending from explosion simulation to the derivation of synthetic observables, the project allows for a direct comparison with astronomical observations thus scrutinizing the modeled scenarios.

Life Sciences

Principal Investigator: Jan Hasenauer, (1)Institute of Computational Biology, Helmholtz Zentrum München - German Research Center for Environmental Health, (2)Center for Mathematics, Technische Universität München, (3)Faculty of Mathematics and Natural Sciences, University of Bonn

HPC Platform used: SuperMUC and SuperMUC-NG of LRZ

Local Project ID: pr62li

Computational mechanistic modelling using systems of ordinary differential equations (ODE) has become an integral tool in systems biology. Parameters of such models are often not known in advance and need to be inferred from experimental data, which is computationally very expensive. The SuperMUC supercomputer enabled researchers from the Helmholtz Zentrum Munich to evaluate state-of-the-art algorithms and to develop novel, more efficient algorithms for parameter estimation from large datasets and relative measurements.

Computational and Scientific Engineering

Principal Investigator: Neil Sandham, Faculty of Engineering and Physical Sciences, University of Southampton (U. K.)

HPC Platform used: Hazel Hen of HLRS

Local Project ID: PP17174149

Shock-related buffeting is a phenomenon that occurs when air passes over the wing of an aeroplane under extreme conditions and can have profound consequences for how wings are engineered and their durability. Leveraging the computing capacities of HPC system Hazel Hen, researchers at the University of Southampton have been investigating this phenomenon using direct numerical simulations.

Computational and Scientific Engineering

Principal Investigator: Qiaoyan Ye and Bo Shen, Fraunhofer Institute for Manufacturing Engineering and Automation, Stuttgart

HPC Platform used: Hazel Hen of HLRS

Local Project ID: PbusRobe

Spray painting is the most common application technique in coating technology. Typical atomizers used in spray coating industries are such as High-speed rotary bell and spray guns with compressed air. High-speed rotary bell atomizers provide an excellent paint film quality as well as high transfer efficiencies (approx. 90%) due to electrostatic support. Small and medium-sized enterprises continue, however, to use compressed air atomizers, although they no longer meet today's requirements from an economic and environmental point of view. It is very important to understand the atomization mechanisms of these two kinds of atomizers, in order to improve the paint quality, to reduce the overspray and to optimize the coating process.

Astrophysics

Principal Investigator: Friedrich Röpke, Zentrum für Astronomie der Universität Heidelberg, Institut für Theoretische Astrophysik und Heidelberger Institut für Theoretische Studien

HPC Platform used: JUQUEEN and JUWELS of JSC

Local Project ID: chwb07

Classical stellar models are formulated in one spatial dimension and parameterize dynamical multidimensional effects. While successful in a qualitative description of how stars evolve, such models lack predictive power. Multidimensional hydrodynamic simulations of critical phases and processes are still extremely challenging but have become feasible due to improved numerical techniques and increasing computational power. This project performs such simulations aiming at an improved understanding of the physics ruling stellar structure and evolution. As an example, a simulation of convective helium-shell burning in a massive star is discussed.

Computational and Scientific Engineering

Principal Investigator: Detlef Lohse, Max-Planck-Institut für Dynamik und Selbstorganisation, Göttingen (Germany), and Max Planck Center Twente for Complex Fluid Dynamics and Physics of Fluids Group, University of Twente (The Netherlands)

HPC Platform used: JUWELS of JSC

Local Project ID: PRA099

Many wall-bounded flows in nature and technology are affected by the surface roughness of the wall. In some cases, this has adverse effects, e.g. drag increase leading to higher fuel costs; in others, it is beneficial for mixing enhancement or transfer properties. Computationally, it is notoriously difficult to simulate these flows because of the vast separation of scales in highly turbulent flows and the challenges involved in handling complex geometries. The studies are carried out in two paradigmatic and complementary systems in turbulence research, Taylor-Couette and Rayleigh-Bénard flow.

Elementary Particle Physics

Principal Investigator: Dr. Stefan Krieg, Forschungszentrum Jülich, Institute for Advanced Simulation, Jülich Supercomputing Centre

HPC Platform used: Hazel Hen of HLRS

Local Project ID: HighPQCD

Nucleons make up more than 99% of the mass of ordinary matter. Computing their properties from first principles, i.e. the theory of Quantum Chromodynamics, is complicated by the non-linear nature of the underlying equations. Only by using supercomputers can we attempt to compute these quantities with the necessary precision. Beyond shedding light on the nature of the nucleons, the results help to resolve some long-standing puzzles in nucleon structure physics and restrict possible models of physics beyond the Standard Model.

Materials Sciences and Chemistry

Principal Investigator: Prof. Dr. Silvana Botti, Friedrich-Schiller-Universität Jena

HPC Platform used: SuperMUC of LRZ

Local Project ID: pr62ja

Direct bandgap silicon can be the key to integrate both electronic and optical functionalities on a silicon platform. Despite considerable effort, achieving light emission from group IV semiconductors has remained unattainable until now. Very recently, ab initio calculations combined with experiments could prove that Ge-rich hexagonal crystal phases of SixGe1-x feature a direct bandgap, tunable in a frequency range coinciding with the low loss window for optical fiber communications. Efficient light emission from direct band gap SiGe could also be shown. Further calculations explore how to engineer light emission by strain and alloying.

Computational and Scientific Engineering

Principal Investigator: Martin Thomas Horsch, Maximilian Kohns, Laboratory of Engineering Thermodynamics, Technische Universität Kaiserslautern

HPC Platform used: SuperMUC of LRZ

Local Project ID: pr48te

Molecular modelling and simulation is an established method for describing and predicting thermodynamic properties of fluids. This project examines interfacial properties of fluids, their contact with solid materials, interfacial fluctuations and finite-size effects, linear transport coefficients in the bulk and at interfaces and surfaces as well as transport processes near and far from equilibrium. These phenomena are investigated by massively-parallel molecular dynamics simulation based on quantitatively reliable classical-mechanical force fields.

Computational and Scientific Engineering

Principal Investigator: Manfred Krafczyk, Institute for Computational Modeling in Civil Engineering of the Technische Universität Braunschweig (Germany)

HPC Platform used: SuperMUC of LRZ

Local Project ID: pr53yu

Flow noise during takeoff and landing of commercial aircraft can be substantially reduced by the use of porous surface layers in suitable sections of the airfoil. However, porosity and roughness of surfaces tend to have an adverse effect on the boundary layer and thus on the lift of wings. This motivates the need to be able to predict the aerodynamic effects of porous segments of the wing surface by numerical methods. Due to the inherent requirements of resolving both the turbulence on the scale of an airfoil and the flow inside the pore-scale resolved porous medium, the simulations run on SuperMUC required more than a billion grid nodes on a locally refined three-dimensional mesh.

Computational and Scientific Engineering

Principal Investigator: Univ.-Prof. Dr.-Ing. habil. Michael Breuer, Department of Fluid Mechanics, Helmut-Schmidt-University, Hamburg (Germany)

HPC Platform used: SuperMUC of LRZ

Local Project ID: pr53ne

The interaction between fluids and structures (fluid structure interaction/FSI) is a topic of interest in many science fields. In addition to experimental investigations, numerical simulations have become a valuable tool to foresee complex flow phenomena such as vortex shedding, transition and separation or critical stresses in the structure exposed to the flow. In civil engineering, e.g., structures are exposed to strong variations of the wind, particularly wind gusts, and such high loads can ultimately lead to a complete destruction of the structure. Scientists are leveraging HPC technologies in order to model wind gusts and to comprehend their impact on the FSI phenomenon.

Computational and Scientific Engineering

Principal Investigator: Detlef Lohse (1, 2), Richard Stevens (2), (1) Max-Planck-Institut für Dynamik und Selbstorganisation, Göttingen (Germany), (2) Max Planck Center Twente for Complex Fluid Dynamics and Physics of Fluids Group, University of Twente (The Netherlands)

HPC Platform used: SuperMUC of LRZ

Local Project ID: pr74sa

Turbulent thermal convection plays an essential role in a wide range of natural and industrial settings, from astrophysical and geophysical flows to process engineering. While heat transfer in industrial applications takes place in confined systems, the aspect ratio in many natural instances of convection is huge. Interestingly, flow organization on enormous scales is observed in, for example, oceanic and atmospheric convection. However, our physical understanding of the formation of turbulent superstructures is limited. In this project, we analyze the flow organization within turbulent superstructures and show that their size increases when the thermal driving is increased.

Elementary Particle Physics

Principal Investigator: Nora Brambilla, Physik Department T30f, Technische Universität München (Germany)

HPC Platform used: SuperMUC of LRZ

Local Project ID: pr48le

Nuclear matter changes at high temperatures from a gas of hadrons into a quark-gluon plasma. For sufficiently high temperatures this quark-gluon plasma can be described in terms of effective field theory calculations assuming weak coupling. In this project, scientists calculate the QCD Equation of State and the free energies of heavy quark systems using Lattice QCD, a Markov Chain Monte Carlo approach for solving the QCD path integral numerically in an imaginary time formalism. By comparing the continuum extrapolated results to weak-coupling calculations in different EFT frameworks, their applicability is being established.