Sound absorption of micro-perforated sandwich panel with honeycomb-corrugation hybrid core at high temperatures

A combined theoretical and numerical study is carried out to evaluate the sound absorption performance of a micro-perforated sandwich panel with perforated honeycomb-corrugation hybrid core (PHCH) at high temperatures up to 700 K. The theoretical model is established based on the classical Maa theory for micro-perforated panels and the method of electro-acoustic analogy. Validity of the model is checked against direct numerical simulations performed on COMSOL Multiphysics. Sound absorption properties of PHCH and its competitors obtained at different temperatures reveal that temperature affects remarkably their low-frequency performance. Average particle velocity in the perforation hole is numerically calculated as a function of temperature, and good agreement between sound absorption peaks and particle velocity peaks is achieved. To further demonstrate the superiority of PHCH in low-frequency sound absorption, the half-absorption bandwidths of PHCH are compared to those of its competitors at high temperatures. The influence of facesheet and corrugation are also studied, illustrating that the former plays a more significant role than the latter. The proposed sandwich structure shows promising engineering applications not only as a load-bearing structure, but also as a sound absorber, even at high temperatures.