Numerical Reproducibility of Human Body Model Crash Simulations

Paper in proceeding, 2021

The numerical reproducibility of a Finite Element (FE) Human Body Model (HBM) was evaluated by
quantifying the variation in model predictions for diverse computer systems at different sites and settings.
Repeated simulations, with varying number of Central Processing Unit (CPU) cores and model decomposition, of
four high severity load cases – a full frontal, near-side frontal oblique and side impact with a full set of driver
restraints, as well as a full frontal with a seat belt only restraint – was carried out on five computer systems. HBM
responses were found to vary randomly with the Number of CPU cores (NCPU), but not due to different hardware
or message parsing interface software at each computer system used. Implemented HBM updates reduced the
variation in the near-side frontal oblique load case. When the NCPU used was fixed, identical results were
obtained from all computer systems. This means the variation of HBM responses is due to the model
decomposition. It is possible to quantify the numerical reproducibility of an FE HBM by repeated simulations,
varying the NCPU and analyzing the coefficient of variation of the responses.