Full Frontal Car Crash Simulation Using LS-DYNA

Many car accidents happen every year due to improper design and selection of vehicle components.The main objective of this thesis is to optimize the front components of the vehicle for crashworthiness by material selection and changing the thickness of components in order to decrease the occurrences of accidents using Finite Element Methods.The safety of a vehicle is important nowadays for the automotive industry.The complicated nature of the physical crash tests of vehicle structures makes design optimization very complex task and nonlinear nature of crashworthiness simulations of vehicle structure makes it impractical to conduct direct optimization on the full nonlinear model of the structure so using finite element method for crash analysis has advantage of saving time and money.Front parts of vehicle absorb maximum part of the energy during crash.With the help of Hypermesh and LS-DYNA,the frontal crash simulations are carried out.Optimizations and analysis are performed to improve the energy absorbing ability of the components.Energy absorption performance is one of the most important indexes in the vehicle safety during impact and in this paper,frontal structure energy performance and structure optimization is conducted.The full vehicle model was established by HyperMesh and simulated in LS-DYNA.Simulation results indicated that modification was need for the original structure to meet the desired requirement.Based on the vehicle model,optimization was implemented,including bumper beam,longitudinal beams and other energy absorbing components.The intrusion rate of dash panel is also analyzed so as to have enough space in the cabin for the safety of the passengers.Finally,after the establishment of the finite element model of the front impact,LS-DYNA is used to simulate the crash analysis and the results of the simulation are shown using HyperGragh.The B-column acceleration,deformation rate of frontal components is analyzed to test if the front collision optimization is met and the results of the pre optimized model is compared with the optimized model and the conclusion is made according to C-NCAP regulations.