Design and Optimisation of Body in White of a four-wheel vehicle

The Body in White (BIW) is a critical component in automobile design, providing essential structural integrity to withstand various loads and stresses during vehicle operation. This paper presents the simulation and analysis of a BIW chassis for a Bolero vehicle using finite element (FE) analysis to evaluate its performance under different loading and boundary conditions. The study focuses on structural and crash analysis to ensure high-quality vehicles that offer adequate protection to passengers during accidents. A geometrical model of the BIW chassis was designed using CATIA V5 software, and simulations were conducted using Ansys Workbench. Modal analysis was performed to observe natural frequencies and mode shapes, while the deformation and stress induced during side and frontal impacts were analyzed. The materials considered for the BIW structure included CP Steel, Duralumin, and a combination of both. A parametric study on weight optimization was conducted, determining the thickness of structural members based on allowable stress and deformation to ensure structural integrity and performance. The results showed an 18.6% reduction in vehicle weight using a combination of Duralumin (dominating in reinforcement parts) and CP Steel (in other areas). The combined material structure demonstrated less deformation in static structure, side crash, and frontal impact scenarios compared to using either material individually at 1.2mm thickness. Additionally, stress levels were observed to be comparatively lower.