论文部分内容阅读
建立了一个新的基于Euler和FW-H方程的旋翼平行桨-涡干扰噪声的计算方法。为减小由于空间离散格式精度和网格密度引起的涡数值耗散,使用了预定涡方法。桨-涡干扰噪声的计算则采用基于声学类比法的FW-H方程。以Kitaplioglu的平行桨-涡干扰试验模型为算例,验证了方法的有效性。在此基础上,分析了干扰距离、涡强、桨尖马赫数和涡旋转方向对桨-涡干扰噪声的影响,并得出结论:增大干扰距离可有效地降低桨-涡干扰噪声,当干扰距离大于数倍弦长时,噪声幅值与干扰距离的平方成反比;涡强仅改变噪声大小,对噪声的脉冲特性无影响;而桨尖马赫数对噪声幅值和方向都有影响,且噪声幅值与马赫数的7次方成正比。
A new method for calculating rotor-blade-vortex interference noise based on Euler and FW-H equations is established. To reduce the dissipation of eddy currents due to spatial discretization accuracy and mesh density, a predetermined vortex method was used. Paddle-vortex interference noise is calculated using the acoustic analogy based FW-H equation. Taking Kitaplioglu’s parallel propeller-vortex interference model as an example, the validity of the method is verified. On this basis, the influence of disturbance distance, vortex intensity, Mach number and vortex rotation direction on the propeller-vortex interference noise is analyzed. The conclusion is drawn that increasing the interference distance can effectively reduce the vortex-vortex interference noise, Interference distance is more than several times the chord length, the noise amplitude is inversely proportional to the square of the interference distance; vortex strength only changes the noise size, which has no effect on the pulse characteristics of noise; and the tip Mach number affects the noise amplitude and direction, And the noise amplitude is proportional to the 7th power of Mach number.