Vibration and acoustic responses of composite and sandwich panels under thermal environment

The paper is focused on the vibration and acoustic responses of the sandwich panels constituted of orthotropic materials applied a concentrated harmonic force in a high temperature environment. The natural frequencies together with corresponding modes are obtained under the thermal stresses by applying the piecewise low order shear deformation theory. The critical temperature is derived to prevent the thermal load excess. And the sound pressure distribution is derived by applying the Rayleigh integral. The analytical solution is verified by the numerical simulations. It is observed that the natural frequencies of the sandwich panel decrease with the increment of the temperature. The interchanges of the mode shapes occur because of the material anisotropy. The peaks of vibration and acoustic responses float to the low frequency domain due to the decrement of the natural frequencies. The influences caused by the high temperature environment on the sandwich panels are deeply discussed.