Topological optimization design on constrained layer damping treatment for vibration suppression of aircraft panel via improved Evolutionary Structural Optimization

Abstract

Light-weight panel structures are commonly used in inlets of the Auxiliary Power Unit (APU) of aircraft. In this paper, a study on topological optimization design of constrained layer damping (CLD) treatment for vibration suppression of aircraft panel based on improved Evolutionary Structural Optimization (ESO) is presented. In the analysis, the volume fraction of CLD material is selected as the constraint condition, and the maximization of modal loss factor is considered as the objective function to enhance damping in the topology optimization model of the structure with CLD treatment, Modal Strain Energy (MSE) method is adopted to deduce the sensitivity of the objective function to design variables, using mesh-independent filter method to solve the checkerboard pattern and the mesh-dependent problem, the ESO with improved evolutionary rate is proposed to search the optimal layout of CLD material, and the correctness and effectiveness of the optimization results are demonstrated through the numerical examples. Compared with conventional ESO, the improved ESO can not only increase the calculation efficiency but also obtain a more reasonable optimized topology geometry. The vibration suppression of the optimized panel is compared with those of the original panel, stiffened panel, and full cover CLD material damping panel and verified by experiments. The results show that the optimized damping panel has a better vibration reduction effect.