Investigation of vertical dynamic behaviour and modelling of a typical indian rail road vehicle through bond graph

Indian Rail transport is one of the major mode of transportation, so it must offer high comfort level for the passengers and the staff. However, the comfort that passengers experience is a highly complex and individual phenomenon. The improvement of passenger comfort while travelling has been the subject of intense interest for many train manufacturers, researchers and companies around the world. Although new techniques in manufacturing and design ensure better ride quality in railway carriages, still it is impossible to completely eliminate track defects or various ground irregularities. The dynamic behaviour of a train also depends on the load and the mechanical systems, such as springs, dampers, etc., which interact with the wheels, the train body and bogies. The present study deals with the effects of railway track imperfections on dynamic behaviour, and investigates the effect of vehicle speed and the rail irregularity on ride comfort through numerical simulation. The numerical simulation of the vertical dynamic behaviour of a typical railroad vehicle will be done by modelling through bond graph technique. The model consists of 17 degree of freedom with wheel set, bogie and car. For assessment of ride comfort Sperling ride index used by Indian Railway is calculated using filtered RMS accelerations. The ride characteristics of the vehicle provide assessment of the dynamic behaviour of the vehicle through analysis of accelerations at the vehicle body, whereas ride comfort assesses the influence of vehicle dynamic behaviour on the human body. The bond graph modelling and its simulation, is performed using SYMBOLS SHAKTI software (1) .