ENVIRONMENT AND ENERGY

In nuclear fusion experiments, researchers routinely heat hot gases up to temperatures of 100 million degrees in order to create the conditions needed for energy-producing fusion reactions. Turbulence is one of the main obstacles on the way to sustaining these conditions reliably. A particular challenge is found in the plasma edge, where turbulence is suppressed by a self-organized transport barrier. Researchers from the Max-Planck Institute for Plasma Physics have made important progress to understanding the turbulence in this region, leveraging resources provided by the Gauss Centre for Supercomputing.

Hydrometeorological extremes, such as droughts and floods are one of the grand challenges of our future and pose great interest and concern for water management and public safety. Hence, the ClimEx project disaggregates the response of the climate system into changing anthropogenic forcing and natural variability by analyzing a novel large-ensemble of climate simulations, operated using High-Performance Computing. The comprehensive new dataset (CRCM5-LE) generated 50 transient independent and evenly likely realizations of the past and the future climate (1950-2099) over two large domains (Europe, Eastern North America) in high spatial (12km) and temporal (1h-1d) resolution. The resulting 7500 model years allow for a thorough analysis of…

Turbulence-chemistry interaction in well characterized partially premixed and premixed laboratory-scale experiments has been investigated numerically by two different methods (M1 & M2) based on the large eddy simulation (LES) technique. It could be shown that the developed transported filtered density function method (M1) is capable of reproducing the turbulence chemistry interaction in the investigated opposed jet flame configurations. The flame resolved simulations (M2) revealed the importance of flame wrinkling and scalar geometry for flame propagation and allowed for further development of sub-filter models for future LES.

Leveraging the high-performance computing capabilities of the HLRS supercomputing infrastructure, scientists of the Theoretical Materials Physics Group of the Paderborn University managed to trace interface defects in amorphous/crystalline silicon heterojunction solar cells. Visualizing the processes with atomic resolution they were able to characterize the processes that compromise the solar cells' efficiency. The findings will help to optimize the solar cells further and to decrease production costs.

Organic Photovoltaics are a promising thin-film solar cell technology since all the constituting layers can be processed from solution processable materials. In order to improve the efficiency of those solar cells it is necessary to optimize their light trapping ability. Different techniques were evaluated in a research project on SuperMUC of LRZ.

The cold combustion in fuel cells is a promising alternative energy technology that does not produce greenhouse gases. One of the main problems of solid oxide fuel cells (SOFC) that reduces the efficiency dramatically is the chromium poisoning. The current collectors in SOFCs are made of stainless steel which contains chromium. By chemical reaction chromium can migrate into the porous cathode and react with its surface. This effect degrades the efficiency and has to be controlled.

Fusion energy is a very attractive option to provide large-scale and CO2-free electricity production for centuries to come. Here, the goal is to mimic the way the sun generates its power under laboratory conditions on earth. To this aim, one confines a plasma (i.e., an ionized gas), consisting of two heavy versions of hydrogen, namely deuterium and tritium, in a doughnut-shaped magnetic cage and heats it to about 100 million degrees. In order for this to work, however, the energy confinement – which is controlled by turbulent transport – must exceed a certain level. 

To study the aerodynamics of vertical axis wind turbines (VAWT) and to carefully characterize the vortex dynamics and decay of VAWT wakes, a team of scientists conducts extensive simulation runs on GCS supercomputers.

Concerns about the present global energy situation and the impacts of climate change are the driving forces for optimizing combustion power plants operation towards maximum efficiency, and thus minimizing the emission of greenhouse gases. Computational modelling of the combustion process in industrial scale combustion systems has become a key technology to achieve this ambitious goal.