某型发动机压气机叶-盘结构优化分析

为快速提高后续批次发动机推重比，针对压气机转子叶-盘-鼓基本结构单元，基于通用有限元软件优化设计平台和循环对称结构静应力分析方法，在不改变叶片气动外形、盘鼓连接半径等强约束条件下，通过合理预设需优化位置的形状和尺寸设计变量，建立从榫头-榫槽连接式叶盘结构到整体叶盘结构的两步优化方法，缩减了优化迭代过程中结构静应力计算用的三维有限元模型规模，提高了优化效率。运用该法对某发动机高压压气机第三级叶盘结构进行优化设计，将最大转速下叶、盘、鼓的离心和气动载荷施加到优化迭代过程中、结构静应力计算用的有限元模型上，同时设置既可线性求解、又能计入接触面上真实应力状态的叶、盘、鼓间的接触，贴合承载和接触实际。采用一阶方法进行优化求解，得到满足约束条件的尺寸设计变量解。对比分析优化前后结构的应力分布，证实该法有效，在保证结构可靠性的前提下，获得了较好减重效果。

Optimization Analysis of Compressor Blade-Disc Structure from an Engine

In order to quickly improve thrust weight ratio of subsequent engines, for the blade-disc-drum structure of compressor rotor, based on general finite element software optimization design platform and cyclic symmetric structure static stress analysis method, under the condition of without changing the aerodynamic shape of blade, the connection radius between disc and drum and other strong constraints, a two-step optimization method from root-groove joint type blade-disc structure to blisk structure has been established by reasonably presetting shapes and size design variables of the locations need to be optimized, which reduces the scale of three-dimensional finite element model used for structural static stress calculation in optimization iteration process and improves optimization efficiency. The structure of a third stage blade-disc from an engine high pressure compressor was optimized based on the method. According to actual working condition of the structure, centrifugal and aerodynamic loads of blade, disc and drums at maximum speed were applied to the finite element model used for structural static stress calculation in optimization iteration process, and the contacts among blade, disc and drums that can be solved linearly was set, and moreover, the real stress state on contact surfaces was included. The first-order method was used for optimization calculation, and the size design variable solutions satisfying constraint conditions were found. By comparing and analyzing stress distribution of the structure before and after optimization, the effectiveness of this method was proved. On the premise of ensuring reliability of the structure, a good weight reduction effect was obtained.