基于拓扑优化的结构加强筋布局降噪方法研究

基于变密度拓扑优化方法,提出了通过优化加强筋布局来降低谐振结构辐射声功率的策略。优化中将加强筋单元的伪密度作为设计变量,约束为加强筋质量上限,所用寻优算法为移动渐近线(MMA)系列算法中的MMA-GC-MMA混合算法。对结构的振动响应使用有限元方法求解,对声辐射使用边界元方法求解,并在此基础上分析了目标函数对设计变量的灵敏度。以加筋箱体为例进行优化,验证了所提方法在降噪设计中的可行性和有效性,并对结果进行了讨论。

STIFFENERS LAYOUT DESIGN FOR NOISE REDUCTION USING TOPOLOGY OPIMIZATION

An optimization approach of stiffeners layout design is proposed based on the topology optimization method to reduce sound radiation power generated by the vibrating structure. The variable density method is employed on the topology optimization problem. Artificial densities of the stiffener elements are adopted as the design variables, and the constraint condition is the upper limit of the total mass of the stiffeners. The optimization problem is solved using hybrid MMA-GCMMA algorithm, which is originated the method of moving asymptotes (MMA) family. The vibrating response of the structures and the sound radiation are solved using the FEM and BEM, respectively. Sensitivity analysis of the coupled acoustic-structural system is derived analytically based on the FEM/BEM results. Examples of stiffened box are presented and discussed. Numerical results show that the optimization approach is effective and feasible.