涡轮盘双轴对称异形孔结构建模与优化

针对发动机轮盘孔结构的应力集中问题,以某高压涡轮盘安装边螺栓孔为研究对象,建立了涡轮盘非圆异形孔数学模型.该异形孔由双轴对称的8段圆弧光滑连接而成,并满足螺栓装配的要求.使用该异形孔模型取代了原螺栓孔.以有限元分析为基础对异形孔进行了优化,得到该轮盘安装边多圆弧异形螺栓孔的最佳形状.结果表明:优化后的多圆弧异形螺栓孔边第1主应力最大值降低了14.8%,孔边应力集中程度显著下降.设计参数灵敏度分析结果表明,与主圆弧相连的过渡圆弧的尺寸对孔边应力的影响较为显著,在设计中应予以重视. 

Modeling and optimization for the structure of biaxial symmetry non-circular hole of turbine disk

In order to resolve the stress concentration of the holes on engine disks,a geometry model of turbine disk non-circular hole was established and applied to a turbine disk flange.The contour of this model consisted of eight biaxial symmetry arcs to ensure smooth connection and bolts assemblage.The geometry of turbine disk hole was improved and optimized with the non-circular hole,using the maximum first principal stress as objective function.The optimization results show that the maximum first principal stress on the non-circular bolt hole inner surface is reduced by 14.8% along with remarkable drop of the stress concentration.The results of design variables' sensitivity show that the sizes of transition arcs connected with main arcs have significant influence on hole edge stress concentration.