Simple Determination on Strain Energy Distribution of Components in Mechanical System Based on Modal Analysis

The experimental modal analysis is widely utilized to analyze the dynamic behaviors of a complex mechanical system. However in order to find components which contribute largely to the total deformation at specific frequencies, the mode shape animation as a result of conventional modal analysis is not good enough. On the contrary, if a precise finite element model of the system is available, which is very seldom, the strain energy distribution of components gives a good insight which components contribute to the total deformation. This paper describes a practical and simple method based on the results of modal analysis to determine such strain energy distribution. After being verified by a numerical model, the method is applied to simple structures and finally an automobile suspension system to show the effectiveness.