发动机风扇噪声进气道传播计算及优化

使用计算气动声学(CAA)方法,分析了典型涡扇发动机风扇噪声在进气道的传播特性,并使用Kriging模型对其外形进行了声学优化。选取典型发动机进气道外形,利用CAA方法求解2.5D线化欧拉方程。分析了发动机进气道近场和远场的噪声水平,空间离散使用6阶紧致格式,时间推进使用4/6阶Runge-Kutta法,计算网格采用二维结构网格。在对典型发动机进气道声传播问题的准确计算的基础上,通过参数化建模、Kriging模型和遗传算法研究了发动机进气道外形对风扇噪声传播的影响,可以作为进一步气动特性和声学特性联合优化设计,以及降噪设计的基础。

Computation and Optimization of Intake Duct Propagation of Aircraft Engine Fan Noise

A CAA method is used in this paper to calculate the engine intake propagation of fan noise and the geometry of intake is optimized using a combination of Kriging model and the CAA method for lower noise while meeting aerodynamic requirements. A typical engine intake geometry is used, the computation of noise propagation in the nacelle is based on a 2.5D LEE formulation, which includes 6-order compact scheme for spatial derivatives, and 4/6 order Runge-Kutta schemes in 2D structured grid. Far-field solution is based on the FW-H equations. Based on these results, some preliminary optimization is carried out for the internal shape of engine nacelle using Kriging-based optimization method.