Title: Effect of vertical track irregularities on the dynamics of freight railway wagon

Authors: Sachin Sudhakar Harak; Sandipp Krishnan Ravi; Satish Chandra Sharma; Suraj Prakash Harsha

Addresses: Vibration and Noise Control Lab., Mechanical and Industrial Engineering Department, Indian Institute of Technology Roorkee, Roorkee – 247667, Uttarakhand, India ' Vibration and Noise Control Lab., Mechanical and Industrial Engineering Department, Indian Institute of Technology Roorkee, Roorkee – 247667, Uttarakhand, India ' Vibration and Noise Control Lab., Mechanical and Industrial Engineering Department, Indian Institute of Technology Roorkee, Roorkee – 247667, Uttarakhand, India ' Vibration and Noise Control Lab., Mechanical and Industrial Engineering Department, Indian Institute of Technology Roorkee, Roorkee – 247667, Uttarakhand, India

Abstract: This paper describes mathematical modelling of a freight railway wagon of Indian railways. The freight wagon is modelled as nine-degrees of freedom system. The equations of motion are derived using Newtonian approach. Rail surface vertical profile irregularity of sinusoidal type is taken as input for both the wheels. The frequencies at which these irregularities occur correspond to the natural frequency of the carbody. The equations of motion are solved by MATLAB using a fourth order Runga-Kutta algorithm with a fixed step size. Time domain responses are obtained for different input frequencies and loading conditions while maintaining the wagon speed constant. The effect of variation of the input frequencies of track irregularities and the loading condition on the dynamic behaviour of the carbody is discussed. It has been observed that the empty carbody gets excited to a severe level of acceleration even at lower resonant frequency and a dense region appears near the resonant frequency peak in FFT. The phase trajectories show quasi-periodic nature of response for empty carbody.

Keywords: freight wagons; dynamic analysis; vertical irregularities; railcar body dynamics; sinusoidal input; resonant frequency; vehicle vibration; track irregularities; railway wagons; mathematical modelling; India; railways.

DOI: 10.1504/IJVNV.2015.070025

International Journal of Vehicle Noise and Vibration, 2015 Vol.11 No.2, pp.133 - 148

Received: 11 Sep 2014
Accepted: 23 Feb 2015
Published online: 24 Jun 2015 *

Full-text access for editors Full-text access for subscribers Purchase this article Comment on this article