Crashworthiness Optimization of Thin Walled Cylindrical Tubes with Annular Grooves under Axial Compression

摘要

In this paper explicit finite element codes of LS DYNA are applied to simulate the crushing behavior of cylindrical metallic impact energy absorbers with annular machined grooves and the validation of the simulation results are done by comparing with experimental and theoretical findings from the literature. Some efforts are made to find the optimum groove geometry of the tubes by considering two criteria such as the maximum absorbed energy per unit mass (SEA) and maximum ratio of average load to maximum load during crushing (CFE). Maximum allowable load during crushing and the geometrical limits that should not exceed some specified boundaries are considered as design constrains. Based on design of experiment technique (DOE) the conditions that the results should be taken are determined and consequently, response surface (RS) models are created to build a composite objective function that considers both CFE and SEA. Genetic algorithm is applied to find the optimal point for the composite function that meets the design requirements.