Study on Proper Arrangement of Damping Material for a Partial Structure with Coupling Loss Factor as an Objective Function

Abstract

P(論文)A structural optimization method of subsystems to realize desired SEA parameters was proposed by the authors in the past studies. This method is based on a combination of SEA and FEM calculation, calculating repeatedly until satisfying the value of objective functions under arbitrary constraints. As a result of applying the proposed method to a simple structure consisting of two flat plates connected in an L shaped configuration, the design variable is taken as the thickness of the FEM element, a subsystem structure with the desired value of the CLF or power flow between subsystems for the one frequency band or multi frequency bands were constructed. However, it is difficult to apply the optimal results to real machine structure because of setting the thickness of the FEM element as the design variable. In this paper, the method is also validated through numerical analyses, using a finite element method, of a multiple plates partially composed of L shaped, the subsystem is grouped into a plural elements for the extracted L shaped part, and the each grouped element is set as a design variable, which should take a discrete value, the total mass is taken as a constraint function in order to minimize CLF23 at one frequency band. As a result of optimization, the sound pressure level was reduced by minimizing the value of CLF23 in the target frequency band.departmental bulletin pape