Crashworthiness analysis and optimization of a novel “cake-cutting” multi-cell tube

Increasing the number of corners can effectively increase the energy absorption of thin-walled tubes. To obtain a thin-walled tube with better energy absorption performance, a novel type of multi-cell thin-walled tube is formed by adding three rib plates, imitating the way of cutting a cake. The rib plates can divide the circular tube into multi-cell tubes with different numbers of multi-cells, and numerical simulations are conducted for the crashworthiness analysis under the axial and oblique impact loadings. The results show that the deformation mode under axial impact is more stable when the number of "cakes" is maximum, and the specific energy absorption is increased by 46% compared with the traditional circular thin-walled tube. Then, a multi-objective optimization framework is employed to find the cutting configuration for better crashworthiness performance. It is found that the optimal multi-cell tube inspired by the “cake-cutting” method can increase energy absorption by 17.4% compared with the original tube. This cake-cutting method provides an innovative designing idea of a thin-walled structure for energy absorption.