Improvement in sound insulation performance of pyramidal truss core cylindrical sandwich structure by adding a frame structure

Cylindrical structures are used in various fields owing to their good mechanical properties. At the same time, the requirements for their acoustic performances continue to increase in the application of cylindrical shell structures. Thus, the acoustic performance and application in sound insulation attract increasing attention. Sandwich cores have been inserted into cylindrical structures to improve the sound insulation performance of the structure. To improve both mechanical and acoustic properties of the cylindrical sandwich structure, a frame structure that strengthens the internal nodes of the pyramidal truss core was added. A theoretical model corresponding to the structure was established to study the sound insulation performance of the structure. The influences of the overall thickness of the structure, number of lattice unit cells, material density, and angle of incident sound waves on the sound insulation performance were analyzed.