Investigation of thermal effects on the steady-state vibrations of a rectangular plate–cavity system subjected to harmonic loading and static temperature loads using a Wave Based Method

Abstract

The steady-state vibro-acoustic behavior of a plate–cavity system under harmonic excitations and static temperature loads is investigated using a Wave Based Method (WBM). The solutions of the governing equations of the vibro-acoustic problem considering thermal effects are derived. The coupled wave based model is constructed based on wave functions and particular solution functions for the acoustic and structural system. The accuracy and efficiency of the WBM are verified by the Finite Element Method (FEM) on a plate–cavity system subjected to harmonic excitations and static temperature loads. Then, numerical simulations are performed to investigate the influence of thermal effects on the vibro-acoustic responses of the system. Further, the design sensitivity is implemented using the WBM. Results show that the developed WBM has a better convergence rate than FEM for the investigated plate–cavity system. Although the temperature-dependent material properties of the cavity have little effect on the plate–cavity resonant peaks of the vibro-acoustic responses, they make the other resonant peaks of sound pressure level responses shift towards higher frequency when the temperature increases. When only the thermal stresses of the structural system are considered, the plate–cavity resonant peaks of the vibro-acoustic responses shift towards lower frequency with increasing temperature. When both kinds of thermal effects are considered, the influence of structural thermal stresses plays a leading role in the plate–cavity resonant peaks of vibro-acoustic responses.