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Happy Anniversary, Hermit!

HLRS Supercomputer Hermit Completes First Year of Operation

On February 24, 2012 Hermit, at that point fastest supercomputer in Germany and all of Europe for civil science and research, was officially inaugurated at HLRS Stuttgart. Delivering a peak performance of more than 1 petaflops, Hermit achieved position 12 on the renowned TOP500 list (11/2011). Though Hermit subsequently gave up its initial ranking on the TOP500 list, the HLRS flagship computer is firmly established in the world of industrial supercomputing: to date Hermit still holds the title as the world’s fastest supercomputer for use in industrial research (TOP500 11/2012, sub-list Industry).

At the day of its inauguration, Hermit was released for official use with the promise to be of great help in research relating to global challenges such as health, energy, environment and mobility. And Hermit lived up to its prediction. One year down the road, approximately 40 projects have taken advantage of Hermit’s petascale computing power providing scientists and researchers with the tools to tackle the big questions of our time. The Cray XE6 system with its 113,664 processing cores has been fully operational and running stably from day one, delivering an average planned system uptime of 99%. With a mean usage capacity rate of 85%, the HLRS HPC system delivers proof that it was designed for sustained performance for real applications. Approximately 60% of scientific users fall into the research realm of engineering. With 30%, physics is the second largest user community relying on Hermit for their research activities.

User Projects

Despite the HLRS workhorse running literally full speed with close to no down time, demand exceeds the available computing time by a factor of 1.5. Users are standing in line waiting for their turn to receive computing hours for their various projects from scientific fields such as materials science, scientific engineering, life sciences, environment, energy and health as well as elementary particle physics and astrophysics. Computing time on Hermit is granted to the researchers by a scientific peer review process. Below are several of the many national and international science projects of breakthrough calibre completed on Hermit:

Project LAMTUR - Laminar Turbulent Transition in AerodynamicsCoundary Layers Project LAMTUR

Project LAMTUR - Laminar Turbulent Transition in Aerodynamics Boundary Layers: Prof. Dr.-Ing. Ulrich Rist and Dr.-Ing. Markus Kloker from the Institute of Aerodynamics and Gas Dynamics of University Stuttgart and their teams are doing simulations on Hermit to achieve a comprehensive understanding of three-dimensional dynamic instability processes, which is a pre-requisite for successful Laminar Flow Control (LFC).

Project Direct Numerical Simulation of the Flow in an Internal Combustion Engine: Prof. Dr.-Ing. Wolfgang Schröder of RWTH Aachen (Fluid Mechanics and Institute of Aerodynamics) and his team use Hermit to study the complex flow field in an internal combustion engine, which has significant influence on the formation of the fuel-air-mixture in the combustion chamber and on the combustion process itself. The scientists aim for a further optimization of modern combustion engines to increase their efficiency and reduce the pollutant emissions.

Project Development and Validation of Thermal Simulation Models for Li-Ion Batteries in Hybrid and Pure Electric Vehicles (ASC-S) - (c) Behr GmbH & Co. KGThermal Simulation Models for Li-Ion Batteries

Project Development and Validation of Thermal Simulation Models for Li-Ion Batteries in Hybrid and Pure Electric Vehicles under leadership of Dr. Jenny Kremser, asc(s (Automotive Simulation Center, Stuttgart), concentrates on the development of a simulation environment for the electro-thermal layout of a lithium ion battery module in a vehicle. The project team pursues the development of optimized design concepts for electrified vehicles to fulfill increasing demands on energy consumption, driving range, and durability.

Hermit for European Research

Hermit qualifies as „Tier-0“ system in the European research infrastructure offered through the Partnership for Advanced Computing in Europe (PRACE), therefore the HLRS HPC system also offers computing power for large-scale scientific projects to scientists and researchers from Europe and beyond. As with the national projects, computing time is allocated to applicants based on a single peer-review process. In the last PRACE Regular Call for Proposals, some record-breaking project allocations of computing core hours were allocated to Hermit for the following projects:

Project UPSCALE: Prof. Pier Luigi
Vidale and his team of scientists from NCAS-Climate (Department of
Meteorology, University of Reading)
and from the Met Office (Exeter) in
the United Kingdom are using Hermit
for compute-intensive simulations in
order to increase the fidelity of global
climate simulations and provide
quantitative information about the
frequency of high-impact events and
their risks. The research activity
 comprises a large series of global experiments (an ensemble), with each member of the ensemble dynamically simulating 27 years of both current and future climates.

Project Large Scale Molecular Dynamics Simulations of NucleationMolecular Dynamics Simulation

Project Large Scale Molecular Dynamics Simulations of Nucleation: Professor Jürg Diemand of the Institute for Theoretical Physics of University Zürich (Switzerland) and his team are running very large (up to 8 billion atoms, millions of time-steps) molecular dynamics simulations of homogeneous nucleation from vapor to liquid. The unprecedented size of the simulations allows the formation of significant numbers of droplets (liquid nano-clusters) under realistic conditions: They can resolve nucleation even at relatively low, more realistic supersaturations and there is no significant depletion of the vapor phase during the simulations. The results will allow to test nucleation theories in a previously unexplored parameter range and hopefully lead to an improved understanding and description of this fundamental process.

Project Plasmonic Ligand-Stabilized Gold Nanoclusters: Prof. Hannu Häkkinen (University of Jyväskylä, Finland) and his team are employing large-scale time-dependent density functional theory calculations to study absorption of light by 2-3 nm gold and alloyed gold-silver nanoclusters that are defined to the molecular precision, i.e., by exact composition and structure. The project aims at breakthroughs in microscopic understanding of the "birth of a plasmon" in nanoscale noble metal clusters. This is of a wide scientific interest, since it will answer fundamental questions pertaining to transformation of nanoscale matter and nanoparticles from "molecular" to "metallic" regime with the concomitant change of optical response of the electrons from discrete transitions to collective behavior. This knowledge is important e.g. for designing and controlling plasmonic nanomaterials and nanosensors.


Hermit is looking forward to about two more years of operation, but it will soon get support from a follow-up system from Cray. The new Cray XC30 – code named Hornet – will increase performance for HLRS users by a factor of between 4 and 5, and will be operational in 2014.

Hermit of LRZ StuttgartCray XE6 system Hermit of HLRS Stuttgart

Technical information on HERMIT