Contribution evaluation of the structure to the vibration based on transfer path analysis

Abstract

Conventionally, the transfer path analysis (TPA) targeted in this study is an experimental method capable of specifying a path to be countermeasured, which has a large contribution to response from among multiple paths by multiplying the external force and the transfer function. Although there are practical examples of application to automobile development, enormous experiments using actual equipment are necessary; it is not easy to grasp the transfer characteristics of vibration and to study countermeasures. Therefore, in this study, we focus on TPA method using Finite Element Method (FEM). In previous study, TPA based on FEM was applied to a mechanical structure having the multiple transfer paths, the structural modification guideline for the path structure itself connecting the subsystem including the vibration source and the subsystem including the vibration receiver was proposed. However, the proposed method is effective only when the contribution of one path is dominant at the target frequency, and no improvement method has been proposed when the contributions of multiple paths are dispersed to the same extent. In this study, to solve these problems, we propose a method to evaluate contribution obtained from TPA using numerical model for each degree of freedom component of transmitted force, by calculating the six degrees of freedom component (three direction force and three direction moment) of the macro transmitted force of the object cross section of each transfer path and the transfer function. By evaluating the contribution for each degree of freedom component of each section force, it is possible to intuitively grasp the phenomenon and to propose an effective structural change proposal for the target degree of freedom, so clarification of the structural change guideline can be expected.

Keywords

• finite element method
• transfer path analysis
• vibration
• contribution
• countermeasure