基于网格参数化变形的单级涡轮多学科可靠性设计优化

基于自由变形技术发展了一种可以协调实现流场、结构分析网格参数化变形的方法,并实现单级涡轮的多学科可靠性设计优化。针对流场分析网格展向积叠的特征,将三维网格变形转化为不同叶高二维截面的网格变形;根据二维流场分析网格的拓扑结构,设计二维控制面,基于叶型设计参数建立叶型控制点、其他控制点伴随叶型控制点移动,实现了网格的参数化变形,避免了网格畸变、提高了网格变形的质量;不同叶高的二维控制面组成控制体,实现三维流场分析网格的参数化变形。采用相同的控制体进行结构分析网格的变形,实现了耦合界面网格协调变形。基于Kriging代理模型进行单级涡轮的多学科可靠性优化,在满足可靠性约束的情况下效率提高4.97%、寿命提高40.86%,证明了方法的有效性。 

Reliability based multidisciplinary design optimization of single turbine stage based on parameterized mesh deformation

On basis of free-form deformation method, a parameterized mesh deformation to morph coordinately fluid analysis mesh and structure analysis mesh was proposed, and reliability-based multidisciplinary design optimization of single turbine stage with parameterized mesh deformation was introduced. According to the extended feature of blade in spanwise direction, the mesh deformation of 3D analysis mesh was translated to the mesh deformation of 2D cross section analysis mesh at different blade height. Control plane for 2D cross section was designed on basis of topological structure of the 2D fluid analysis mesh. The coordinates of blade profile control points were calculated by aerodynamic design parameters. The movements of other control points in 2D control plane were obtained according to the movement of blade profile control points in order to improve the quality of the deformed mesh. The mesh deformation of 3D fluid analysis mesh could be carried out by the control volume composed of 2D control planes at different blade heights. Structure analysis mesh was morphed by using the same control volume for 3D fluid analysis mesh deformation in order to obtain the coordinate mesh deformation on interface mesh. Reliability-based multidisciplinary design optimization with proposed parameterized mesh deformation method was used to optimize single turbine stage. Results showed that the efficiency was improved by 4.97% and the blade life was improved by 40.86% under satisfying the reliability constraint, proving the effectiveness of the developed method.