ISOGEOMETRIC ANALYSIS OF VEHICLE IMPACT

Abstract

Isogeometric Analysis is a very e cient tool developed in the area of computational mechanics. In this method design and analysis can be integrated by using NURBS technology for geometric design and isoparametric concept of the nite element method as analysis tool. Firstly static analysis is formulated for structural crash worthiness analysis of vehicle and then this analysis is extended for the dynamic impact analysis by dividing time into nite number of time segments and applying analysis at each discrete time points. MATLAB is used for generating mesh and applying the boundary conditions. Solving the system of equations give stress and displacement results. The solution results are stored in .vtu le which can be visualised in Paraview. Although NURBS technology is very e cient in isogeometric analysis but trimmed NURBS fail to generate analysis suitable mesh automatically. This problem is solved by using T-splines as basis for geometry creation and analysis mesh generation. T-splines are forward and backward generalisation of NURBS technology. T-splines also solve the problem of local re nement. In this article T-spline model of a vehicle is generated using T-spline plug-in for rhino3d and the model is also meshed. User element implementation of Abaqus/CAE is used to apply the loading conditions, boundary conditions on the model. The simulation solves the system and results of isogeometric analysis are visualised on ner nite element mesh. For the vehicle impact analysis system here energy is domain of study. The kinetic energy of impacting vehicle generates strain energy to deform the vehicle structure and frictional and viscous dissipation reduce generation of strain energy that cause lesser deformation to the vehicle structure.