An adaptive thick shell element for crashworthiness assessment of laminated composites

The  automotive  industry  is  strongly  dependent  on  efficient  numerical  tools  in  order  to  assess  the  crashworthiness  of  laminated composites. Unfortunately, to achieve predictive assessments of fracture in laminated composites one must resort to computationally costly, high-fidelity  layered  models,  which  in  practice  makes  full  vehicle  crash  simulations  very  difficult  (or  even  impossible).  One  solution to this is to use an adaptive modelling technique where an initially coarse model is automatically refined, when and where needed, during the analysis.

In this context, we have developed an LS-DYNA® user element which can be adaptively refined through the thickness to allow for both so-called  weak  discontinuities  (discontinuities  in  strain  at  material  interfaces)  and  strong  discontinuities  (discontinuities  in  displacements, i.e. delamination cracks). Furthermore, we have proposed a remedy to the numerical instabilities which arise from using adaptive refinement in a dynamic explicit solver. This adaptive element proves capable of reproducing the result of high-fidelity models, although at a lower computational cost.

Johannes Främby, Jesper Karlsson, Martin Fagerström
Research area
Publication type
Published in
16th International LS-DYNA® Users Conference
Year of publication

Safer – Vehicle and Traffic Safety Centre

SAFER is the open research arena where researchers and expertise work together to create safe mobility. Our traffic safety approach covers people, vehicles and the infrastructure – and together we contribute to safer road transports and smarter, more sustainable cities.

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