船舶螺旋桨低频噪声研究

Study of Low-frequency Noise Induced by Marine Propeller

螺旋桨低频噪声构成了船舶中高速航行时整个辐射噪声中的重要分量。螺旋桨的低频离散谱噪声是由船尾伴流场和叶片的相互作用引起的 ,而低频宽带噪声是由船尾粘性湍流场和叶片的相互作用产生的。利用升力面理论和声学方法得到的离散谱噪声的预报公式 ,对螺旋桨直径、侧斜、纵倾变化对离散谱噪声的影响作了数值计算 ,并得到了工程上有实用意义的结果。在分析螺旋桨低频宽带噪声成因的基础上得到了理论计算方法 ,并作了数值计算。整个方法对船舶螺旋桨噪声预报提供了工具 。

The low frequency noise of propeller has constituted the main part of radiated noise of middle or high speed marine. The low frequency discrete noise of the propeller is induced by the interaction between blades of the propeller and wake of the marine, and the low frequency broadband noise of the propeller is produced by the interaction of blades and turbulent field of the marine stern. Using a combination method of the lifting surface theory and acoustic technique, the effects of different diameters, skews and rakes on the discrete noise of the propeller are studied by the numerical method and some useful results for engineering are presented in this paper. According to mechanism of low frequency broadband noise of the propeller, theoretical analysis method is given and numerical calculation of the noise is worked out as well. The methods will not only make a key tool for noise prediction, but also play a role for noise control of the propeller in engineering project.[WT5HZ]