Topology Optimization of Free Damping Material Based on Optimality Criteria Method
ZHANG Zhifei1, 2, NI Xinshuai2, XU Zhongming1, 2, HE Yansong1, 2, Yuan Qiong 2&Li Yaoguang 2
1. State Key Lab of Mechanical Transmissions, Chongqing University, Chongqing 400030, China;2. College of Mechanical Engineering, Chongqing University, Chongqing 400030, China
Abstract：Based on SIMP, a topology optimal model was established with maximum modal damping ratio as goal, damping material volume as restriction and densities of damping cell as design variables. The sensitivity of modal damping ratio to density of damping cell was analyzed, and the updating criterion was derived. Then, the topology optimization program based on optimization criteria algorithm was written using Direct Matrix Abstraction Program of MSC.Nastran. The structure-acoustic coupling model, consisting of aluminum plate and the acoustic cavity, was selected as an example. With this program, the arrangement of the damping material on the aluminum plate was optimized to maximize the damping ratio of the first bending mode by finite element method, which is validated by experiments. These two separate damping treatments: fully damped and partly damped after optimized, was compared with no damp material. After treated, the peak pressure at the reference point was respectively reduced 110.6Pa and 107.7Pa in simulation, while 22.47Pa and 20.91Pa in experiments. The comparison of them indicated the topology optimization program was valid.
2013, Vol. 32 
