Equivalent mixing of experimental models in dynamic substructuring : dissertation

english

doktorska dela

2021

dissertations   experimental modelling   frequency based substructuring   singular vector transformation   structural dynamics   transfer path analysis   virtual point transformation

Univerza v Ljubljani, Fakulteta za strojništvo
(Obvezni izvod spletne publikacije)

Evaluation of structural dynamics is an essential step in the design of modern complex mechanical systems. The ever increasing demand on optimization of vibro-acoustic performance has led to numerous advancements in noise, vibration and harshness engineering in the past decade. One of the most promising frameworks is dynamic substructuring, within which complex dynamic systems can be analyzed by characterizing each subsystem separately. This work covers an experimental approach to frequency based substructuring and transfer path analysis. Through experimental modelling the real dynamic properties of each subsystem can be obtained directly, without the need for a complex numerical model. Several approaches to experimentally model an interface within frequency based substructuring are introduced. An expansion to virtual point transformation is presented, where directly measured rotation response is included in the transformation. An novel transformation method named the singular vector transformation is presented on a coupling and decoupling application. Furthermore, an approach to identifying a set of full-field frequency response functions based on system equivalent model mixing is presented. Finally, an application of component-based transfer path analysis is presented on the source characterization of an electric motor. The main limitations and advantages of each methodology are outlined. Based on the provided observations, both frequency based substructuring and transfer path analysis can be an integral part of the development process.

15.05.2023