Multi-discipline optimization of sandwich cylinders under a point force excitation

The aircraft fuselage was idealized as a sandwich cylinder and the minimization of the inner sound pressure of the cylinder was studied. Subjected to a point force excitation, the inner sound pressure of the sandwich composite cylinder was predicted using the FEM/BEM. The acoustic transfer vector method was adopted in the numerical model. The predicted results were validated with the experimental results. Using the verified numerical model, the structural parameters including core properties, core thickness, sandwich layup and fiber orientation, were studied for their influences on the inner sound pressure. Finally, an optimization method integrating the genetic algorithm and acoustic transform vector method were developed to minimize the inner pressure of a fuselage section. It has been demonstrated that the optimization method can improve the computation efficiency and give a good compromise between the weight, the mechanical performance and the acoustic properties of the sandwich fuselage.