*Contact Author e-mail: vinod_banthia.aae.et@msruas.ac.in
Crash safety is an important domain in the field of automotive engineering. Finite Element Analysis (FEA) and Lumped Parameter Model (LPM) are two most widely used methods for determining the crashworthiness characteristics of a car. When compared to FEA, LPM is less accurate in predicting the exact dynamics of crash. However, LPM has been widely used in industry since 1970 to predict crash performance during development stages.
An attempt is made in this paper to develop an LPM representation of crash energy absorbing structure for frontal crash. After validating FEA results of axial crushing of a square tube with the experimental results, LPM model for the same tube was created using the stiffness characteristic of the tube obtained from FEA analysis results.
Next, two configurations, one with two and another with five square tubes, were analysed using FEM and LPM. For developing LPM, first, crush characteristics of a single square tube was obtained using FEA.
Results from use of LPM model were compared with the FEA results and it was found that LPM is capable of predicting crash phenomenon when the stiffness is obtained from software simulation instead of experiments. The results of crushed distance and force-displacement characteristics from FEA and LPM were found to match well. CPU time required of LPM was a fraction of that for FEM.
Crashworthiness, Lumped Parameter Model
