Interface Forces Identification Using Component TPA In-situ Method for Transfer Patch Analysis (TPA)

Résumé

The marine transport industry uses a lot of subsystems such as engines, that produce tonal vibrations which propagate through different paths into the receiving structure. The analysis of how vibrations are transmitted between components is required in many engineering applications. TPA methods are mainly used to solve NVH problems using sub-structuring applications. The most challenging part of a TPA analysis is estimating the equivalent forces at the contact points between the active and the passive side. Component TPA In situ Method calculates these forces by inverting the frequency response functions (FRFs) measured at the passive subsystem, relating the motion at indicator points to forces at the interface. However, matrix inversion could pose problems due to the ill-conditioning of the matrices leading to inaccurate results. In this paper, a TPA model is established for an academic system consisting of two plates linked by four springs. A numerical study has been performed to investigate the matrix inversion problem. Several parameters are studied and discussed to improve the equivalent forces identification, such as the singular value rejection, and the number and position of indicator points chosen and used in the inversion matrix.