Evaluation of frequency excitation of helical suspension spring using finite element analysis

摘要

Frequency response analysis is a technique used to determine the steady-state response of a linear structure to loads that vary harmonically with time. The aim is to calculate the structure's response at several frequencies and obtain results as response quantity versus frequency or time using finite element analysis. Peak responses are then identified on the graph and stresses reviewed at those peak frequencies. This paper discusses the modal and harmonic or frequency response of helical suspension spring of rail road vehicle using finite element tool ANSYS for different harmonic forces on inner and composite springs. The experimental result of accelerometer has been recorded for maximum speed of 80 km/hr determines excitations for amplitude of acceleration of suspension system versus time. Modal analysis finds the natural frequencies of spring for different modes of vibration for inner and composite assembly of spring and harmonic analysis of undamped suspension system reveals peak amplitude of stress and acceleration for the frequency range of 0 Hz to 50 Hz. The analysis reveals that the maximum amplitudes occurred at frequency of 40 Hz for inner spring and 35 Hz for composite spring which is nearer to theoretical natural frequency of inner spring 38.06 Hz.