Effect of *IMPERFECTION and Various Contact Algorithms on the Simulation of Quasi-Static Collapse of Thin-Walled Energy Absorbers Using ABAQUS/Explicit

Numerical modelling and simulation of the quasi-static collapse of thin-walled energy absorbers to determine their crashworthiness performance is a challenging task. For this purpose, commercially available Finite Element (FE) software employs an implicit/explicit time integration scheme. Simulations become challenging because multiple modelling parameters are involved. Choosing the correct alternative out of the available modelling and simulation parameters makes this process complicated. In this study, two such modelling parameters, *IMPERFECTION and various contact algorithms available in ABAQUS/Explicit, are considered. The influence of these two parameters on crashworthiness response of quasi-static collapse of mild steel square crash-box is investigated by carrying out numerical simulations using ABAQUS/Explicit. To check the effect of these parameters on numerical simulation post-processing results, crashworthiness behaviour is studied. To ensure the simulation to be quasi-static in nature, the ratio of kinetic and artificial energies to the internal energy of the system is considered. Overall simulation time for each simulation is also taken into account. Numerical model used in this study to simulate the quasi-static collapse of thin-walled square crash-box is validated by comparing the obtained results with the available theoretical, experimental and numerical literature. It is observed that, the explicit FE simulation of quasi-static compression of the crash-box is affected to a great extent by these modelling parameters.