Study on Sound Transmission Loss of Lightweight FGM Sandwich Plate

Lightweight sandwich structure is widely used to prepare the body of moving vehicle, which requires its light weight, high mechanical strength, good sound transmission loss and other multi-functional characteristics. Functionally gradient materials can effectively reduce the stress mutation caused by mismatching of material properties, so the mechanical strength of the structure can be improved. The main objective of this research work is focused on sound transmission loss analysis of ribbed plate functionally graded material (FGM) sandwich plates filled with air, wherein two types of FGM sandwich structures are considered, which include one with FGM face sheets and homogeneous metal core, and the other with FGM core and homogeneous face sheets. Firstly, the acoustic projection loss of the sandwich panel filled with a cavity is analyzed by simulation software, and compared with the existing numerical results, the validity of the model is verified. Based on the simulation model, the effects of boundary conditions, the spacing between the stiffeners, the gradient index of functionally graded materials, and the thickness ratio of the panels to the stiffeners were analyzed.