Tiger Team: tt-h2-diffusion
Accelerating the Simulations of Processes of Hydrogen Diffusion
The goal of the work supported by the tigerteam was carried out in the frame of the Q-PETE experiment at INR, to investigate the diffusion parameters of hydrogen isotopes, which penetrate through metal membranes. The most important parameter which was analyzed and evaluated is the dimensionless diffusion constant D*. The evaluation of this parameter has required code development for different mathematical methods, which involve matrix inversion. Several Q-PETE experiment setups were tested, with different geometric and transport parameters. The typical computational time of the program for solving the transport equations was about 36 hours for D* in the range [0,1].
The tuning of the D* parameter was based on stability criteria, which could be found while exploring different matrix inversion methods, as explained in references  and . Finally, a full simulation with the related suitable time step takes currently 40 s on bwUniCluster. This has to be compared with the old simulation time where the computations of a similar case took about 6 hours for a D* in the range [0,0.25].
 Axel von der Weth, Daniela Piccioni Koch, Frederik Arbeiter, Till Glage, Dmitry Klimenko, Georg Schlindwein, Volker Pasler, Norbert Prothmann, Kevin Zinn, Numerical Solution Strategies in Permeation Processes; Defect and Diffusion Forum (Volume 413), December 2021, https://doi.org/10.4028/www.scientific.net/DDF.413.29
 Till Glage, Axel von der Weth, Frederik Arbeiter, Daniela Piccioni Koch, On the Analytical Inversion of Solver Matrices Used in Numerical Approximations for the Diffusion Equation; Defect and Diffusion Forum (Volume 413), December 2021, https://doi.org/10.4028/www.scientific.net/DDF.413.3
Members of the Tiger-Team:
Arbeitsgruppe Messtechnik und experimentelle Methodik, Institut für Neutronenphysik und Reaktortechnik (INR), KIT; Dr. Daniela Piccioni Koch, SCC, KIT, HPC Competence Center Ing