Fig. 1: Model of arc welded curved girder
Fig. 2: Model of high speed laser welded sheet
Results of the project
The results of the test cases with explicit analysis provided the following results: The scaling behaviour in the double-logarithmic scale is linear with nearly constant gradient up to 4080 cores (Fig. 3). Above 96 cores the model MDB with 1 million elements provides a better scaling than the model EDB with 200 000 elements due to the fact that the number of elements per core domain is larger in this case. Regarding the parallel efficiency (the ratio of speedup and number of cores), the larger model has a ratio of 0.45 at 768 cores, and at the highest number of cores (4080) a ratio of 0.4.
Fig. 3: Speedup of elapsed time for the explicit analysis
As a result of the project in general, recommendations for the number of cores in order to obtain the optimal performance are provided and the expected speedup is given. Both the number of the cores and the speedup depend on the model type.
The overall effort for welding analysis on HPC is now much better known with the help of this SHAPE project , leading to the ability of a more accurate cost estimate of welding consulting jobs.
This project provides a good basis for further investigations in high performance computing for welding structure analysis.
This work was financially supported by the PRACE project funded in part by the EU’s Horizon 2020 research and innovation programme (2014-2020) under grant agreement 653838.
 Loose, T. ; Bernreuther, M. ; Große-Wöhrmann, B. ; Göhner, U.: SHAPE Project Ingenieurbüro Tobias Loose: HPCWelding: Parallelized Welding Analysis with LS-DYNA, SHAPE White Paper, 2016, http://www.prace-ri.eu/IMG/pdf/WP220.pdf
 Loose, T.: Einfluß des transienten Schweißvorganges auf Verzug, Eigenspannungen und Stabilitiätsverhalten axial gedrückter Kreiszylinderschalen aus Stahl, Dissertation, Universität Karlsruhe, 2007
 Loose, T. ; Mokrov, O. ; Reisgen, U.: SimWeld and DynaWeld - Software tools to set up simulation models for the analysis of welded structures with LS-DYNA. In: Welding and Cutting 15, pp. 168 - 172, 2016
 http://www.fabweld.eu ; http://www.dr-loose-gmbh.eu