一种快速计算螺旋桨气动声学特性的数值方法

A fast numerical method for calculating propeller aerodynamic and acoustic characteristics

在低速螺旋桨性能计算方面,涡格法是快速有效的方法。但是在计算表面压力分布时,传统的涡格法遇到了无法克服的困难。本文推导出在叶片表面布置分布涡强的方法,既保持了涡格法计算快的优点,又较好地计算出叶片表面压力分布。以此为基础,本文采用FW-H方程忽略四极子效应的时域解法,使用与气动计算相同的表面网格,快速解出了螺旋桨的远场声学特性,计算结果与实验结果符合程度较好。说明该一体化方法可以用于螺旋桨噪声机理分析和低噪声螺旋桨设计,从而为分析螺旋桨噪声机理和设计低噪声螺旋桨提供简便工具。

This paper deals with a fast numerical method for calculating propeller aerodynamic and acoustic characteristics. The traditional vortex lattice method puts vortexes of unknown strength on blade surface, which can calculate total thrust and torque coefficients of propeller. Because of ignoring the effects of dipoles, it can not calculate surface pressure distribution. A new lift surface technique, which was proposed by the authors first, distributes vortexes of unknown strength density on blade surface and makes better results of pressure distribution. Based on these pressure distribution and Farassats solution of FW-H equation, the sound pressure lever of low speed propeller can be calculated in a few minutes with fair agreement with experiments.