Simulation and Analysis of the Cabin Typical Structure under Vibro-acoustic Combined Environment

Abstract

Vibro-acoustic combined environment is the main source of vibration during the launch and high-speed flight of aircraft, in order to determine the experimental standard, this paper will utilize the famous vibration and acoustic analysis software--LMS.SYSNOISE, and combine the large-scale finite element analysis software--MSC.PATRAN&NASTRAN, to carry out numerical simulation of random vibration from a shaker plus reverberant acoustic field to the cabin structure. Based on combination of finite element and boundary element technology, we establish the coupling finite element and boundary element model of cabin structure. Through analyzing the coupled finite element and boundary element formulations, as well as the principle of stochastic analysis, the coupled formulations can be transformed into the form that expressed as input-output power spectrum density (PSD). By the mathematical formulation deduced we can calculate nodal response PSD of the coupling model under random vibro-acoustic combined environment, it solved the problem that SYSNOISE cannot calculate at the situation when the structure is suffering two different kinds of random excitations simultaneously.