拟牛顿法在航空发动机特性仿真中的应用

航空发动机特性仿真中常用牛顿迭代法求解非线性方程组,牛顿法每一步迭代计算都需要计算Jacobi矩阵,这需要多次发动机气动热力过程计算.因此避免大量重复计算Jacobi矩阵可以减少发动机计算整机的气动热力计算次数,从而提高发动机特性计算的速度.文中采用基于Broyden原理的拟牛顿法求解发动机非线性方程组,这种方法可以直接求出第一步迭代后的Jacobi矩阵,从而大幅度提高计算速度.将拟牛顿法应用于某型涡喷和涡扇发动机特性计算,通过分析计算结果,证明了采用拟牛顿法可以提高发动机特性模拟的计算速度.

Application of Quasi-Newton Method to Aero-engine Performance Simulation

Newton iteration method is often used to solve the non-linear equations of engine cooperation in the aero-engine performance simulation.In order to obtain Jacobin matrix,Newton iteration method must calculate engine aerothermodynamic process several times in every iteration.So,avoiding Jacobin matrix calculation can reduce the number of aero-engine performance simulation.This article uses Quasi-Newton method based on Broyden's principle to obtain Jacobin matrix,this method can calculate Jacobin matrix directly after the first iteration,consequently,it can improve the speed of aero-engine performance simulation.This method was applied to the performance simulation of turbojet and turbofan engine.By analyzing the calculation results,it is proved that Quasi-Newton method is a favorable way to reduce the number of performance simulation.