Everyone wants to run more simulations, faster and more accurately, but speed and accuracy are usually computationally incompatible. Crash simulations are a case in point, small element sizes are required to capture local buckling etc. and, as a consequence, small stable time increments lead to long run times. Such long runtimes preclude the use of iterative strategies such as DOE or optimization to find improved design proposals. During this webinar Jing Bi, Senior Portfolio Technical Specialist, CSO Structure, SIMULIA will present a new “patent pending” method that accelerates finite element explicit crash simulations by one or two orders of magnitude to enable multi-disciplinary concept and optimization studies.
A coarser mesh would drastically reduce runtime, but with a severe penalty of a loss of accuracy. A hypothesis was proposed that this discretization error could be corrected based on geometry and material properties. A machine learning algorithm was used to determine the correction factors for the coarse mesh representations of 100’s of scenarios, such that outputs (reaction forces, deformations and absorbed energy) of the fine mesh matched the coarser mesh within a 15% error bound.
To illustrate the approach it was applied to a conceptual early design stage automotive crash structure which contained around 20 components, undergoing a 55 km/h frontal crash. The objective was to reduce impact accelerations to 35 g and limit the structural deformations to 550 mm; a complex problem as changes in a single component can change the collapse sequence of the beams, thus creating a bifurcation in the crash response. The coarse mesh approach, along with the Adaptive DOE technique that was used, allowed the optimization process to be reduced from a month to less than an hour.
The webinar will highlight key topics which will be of interest to all engineers: