Explicit finite element method for vehicle crashworthiness

Based on the continuum mechanics, governing equations of vehicle collisions were set up and the weak form of the equilibrium equations was found. Through explicit discretization of space and time, finite element equation was obtained. By utilizing dynamic explicit integral, nodal displacements were calculated explicitly, which avoids the convergence problem caused by highly non-linear factors including material, geometry, boundary. Also the Courant stability condition for thin-shell element was discussed. The design method of crashworthy structure longitudinal compress deformation, longitudinally absorbing energy was proposed and numeric simulation on an example was carried out. The results show that the design method can realize self-structure passive safety and the explicit finite element method is an effective way for structure crashworthiness research. But it is necessary to carry out some crash tests so as to modify the numeric model and!improve simulation accuracy.