Vibration analysis of a trailer bogie of a lrv

The transportation is one of the most significant problem in Istanbul which is one of the biggest metropolis in the world with a population over 15 million. The main reason of the that problem is that people are not always used public transportation in daily life. Because of public transportation is not widespread and not sufficient when it is compared to the population. Railway is one of the public transportation and provides reliable, comfortable, rapid and environment friendly service. These systems have independent lines in the urban traffic. Therefore the importance of this system is increasing gradually compared to the other ones. Rail systems have critical importance in solving the problem of public transportation for Istanbul where new passenger cars hit the roads day by day. Enhancing the urban rail transportation is also causing some specific problems with serious contribution for decreasing the traffic problem. The main problem of the rail systems is vibration. In case of any preventation, this can affect on both passenger comfort and environment. In this thesis, vibration analysis of the trailer bogie for the Istanbul tram that is designed (industrial and engineering) by Istanbul Ulasim A.S. was performed. The analyses performed in this thesis are experimental modal analysis, finite element analysis (FEA) and torsional stiffness analysis. In experimental modal analysis, two different conditions was carried out to obtain the free-free condition. In the first modal test, bogie frame was hanged on tow hook of crain by means of spring and rope. In the secod test, measurements were performed by means of mounting the bogie frame on two pieces of rubber on the ground. It was determined which method of the two tests did converge these two tests to the results of finite element method? In the finite element analysis, a 3D model of trailer bogie is modelled in the Catia software. Then, mesh model of trailer bogie was obtained using Hypermesh software. vibration characteristics of trailer bogie was obtained by solving the mesh model in Radioss software. The analyzed data which are modal frequency, modal shape and damping ratio, were depicted as graphics by using Hyperview software. In torsional stiffness analysis of the bogie frame; three different loading cases were applied on the bogie mesh model was obtained using Hypermesh software. One of these cases is to ensure structural strength of the bogie frame according to standard of the bogie frame structural requirements in case of the twist of line. The rest of the other cases are; to investigate the torsional stiffness of the bogie frame using constraints preferred in automotive chassis. In the results of the thesis, firstly, experimental data of designing undergo bogie and FEM results were compared in order to get optimum bogie model. Secondly, results of studied bogie in this work and the others which in literature were compared and to intent to find out advantages which were presented in the thesis.