湍流进流诱发的二维水翼振动噪声特性研究

Study on the 2D Hydrofoil Vibration and Noise Induced by Ingested Turbulence

为研究螺旋桨流噪声,以螺旋桨的基本构型单位二维翼型为研究对象,研究其在不同工况下的振动噪声规律。以Lighthill声类比理论为基础,应用计算流体力学软件CFX和声学仿真软件LMS Virtual Lab分别模拟在不同工况下翼型的流场和声场分布。取翼型非定常脉动力作为声源,然后采用边界元方法分别求解翼型流噪声和振动噪声。结果表明,噪声水平随速度和翼型攻角的变化呈现较为明显的规律;相比考虑翼型振动时的振动噪声,忽略翼型振动影响的情况下流噪声水平偏大。

In order to study the flow noise of propellers, the rules of vibration and sound radiation of a 2D hydrofoil, which is the basic composition unit of the propeller, were investigated in different working conditions. Based on Lighthill＇ s acoustics analogy, the flow field and acoustic field of the hydrofoil were simulated by means of the computational fluid dynamics software CFX and the acoustic software LMS Virtual Lab. Taking the unsteady fluctuating pressure induced by the fluid on the hydrofoil as the noise source, the boundary element method （BEM） was used to compute the flow noise and the vibration noise of the hydrofoil. The results show that the sound pressure change of the noise has distinct rules with the velocity and the incidence angle change. The sound level of the flow noise neglecting the influence of the hydrofoil vibration is higher than that of considering the influence of the vibration noise.