摘要
研究了导管螺旋桨低频离散谱噪声辐射机理和预报方法。依据线性声学原理,导管螺旋桨噪声场为螺旋桨直接辐射噪声与导管散射噪声之和,并利用速度势面元法分析流场,得到导管螺旋桨非定常力,将其作为FW-H方程的源项,求解得到螺旋桨直接辐射声。导管散射声通过Kirchoff积分方程求解获得。由于导管桨的导管是短导管,其算例分析计算表明,低频情况下导管散射声级远小于螺旋桨直接辐射声级。并将导管螺旋桨离散谱噪声级与测量所得的实桨离散谱噪声级进行了比较,证实导管螺旋桨离散谱噪声理论预报结果能够较合理的反映实桨离散谱噪声的量值。
The mechanics and prediction methods of duct propeller low-frequency discrete spectrum noise are studied. The acoustic pressure field of duct propeller is split into the propeller radiated field and the duct scattered field based on the linear acoustic principle. Firstly the flow field is analyzed with potential-based panel method to get the unsteady force, and then the pressure data are used as the sources for Ffowcs Williams-Hawings formulation to predict the propeller radiated field, and the duct scattered field is obtained by Kirchoff integral equation. Through the analysis and calculation of duct propeller case, the outcome was obtained that the duct scattered sound field is a small quantity compared with propeller radiated sound field under low-frequency condition and short duct; Also the discrete spectrum noise level of duct propeller is compared with full-scale propeller＇s discrete spectrum noise level by experiments, conforming the prediction results of duct propeller discrete spectrum noise level are able to reflect the full-scale propeller＇s discrete spectrum noise level properly.
出处
《声学学报》
EI
CSCD
北大核心
2009年第2期117-123,共7页
Acta Acustica
