基于拓扑优化的冲压发动机主安装节承力结构设计

Structure design of main mounting in ramjet engine base on topology optimization

针对冲压发动机主安装节承力结构优化,开展集中力扩散结构设计。首先采用工程方法设计放射肋扩散结构方案,然后开展拓扑优化设计。通过平板结构优化算例验证适合此类工程问题的内力均匀性约束条件,采用全域粗网格模型求解优化设计域、精细网格模型求解结构方案的二轮优化迭代的拓扑优化方法,得到最终优化结果。通过工程设计法与拓扑优化方法的对比,证明拓扑优化方法更适合处理多方向、多工况载荷的集中力扩散结构工程问题。结构拓扑优化方案对比放射肋方案:结构质量减轻2.6;对应最大载荷(工况3)的结构最大变形量减少4.4,结构最大应力减少10;集中力扩散效果更好。设计方法的有效性得到验证,为集中力扩散结构优化探索出实用的设计思路和方法。

In order to optimize the load-bearing structure of the main mounting joint in ramjet engine,the structure design of concentrated force diffusion was carried out.Firstly,the radial rib structure was designed by engineering method,and then the topology optimization was carried out.The constraint condition of internal force uniformity suitable for the diffusion structure was verified by the optimization example of plate structure.The global coarse mesh model was used to get the design domain and the fine mesh model was used to optimize structure,and the final scheme was obtained through two rounds of optimization iterations.Through the comparison between the engineering design method and the topology optimization method,it is proved that the topology optimization method is more suitable to deal with the concentrated force diffusion structure with multi-directions and multi-condition loads.Compared with the radial rib scheme,the topology optimization scheme can reduce the structural mass by 2.6,the maximum deformation under the maximum load(case 3)by 4.4,the maximum stress by 10,and the effect of concentrated force diffusion is better.The effectiveness of this method has been proved,which provides a practical design idea and method for the structure optimization of concentrated force diffusion.