Bus vibrations study-finite element modelling and determination of Eigen pairs

Abstract

This paper describes the finite element idealization of a typical Indian transport bus and uses this model to predict the first few eigenpairs. The eigenvalue problem has been solved by the simultaneous iteration method and Lanczos' scheme and by using two different finite element models. The first model consists of chassis elements, the axles, the suspensions and the tyres, the mass of the superstructure being lumped at the appropriate nodes. The second is a more comprehensive model in which, in addition to the chassis, axles, suspension and tyres, the framework of the superstructure and the plates constituting the bus body and floor have been taken into account. The eigenfrequencies obtained by using both these models match well with frequencies arrived at experimentally.