水下高速目标对转螺旋桨空化线谱频率理论预报

水下高速目标对转螺旋桨常工作在空化状态,其噪声线谱由前后桨相互作用及前后桨与船舶尾流场的相互作用引起。通过Goldstein的声相似方程,将空泡看作螺旋桨的一部分,对空化条件下水下对转螺旋桨的线谱频率进行了理论预报。推导出了远场条件下单极子源性质的声源所产生的声压表达式,得到了其线谱预报频率。对实测水下高速目标进行了线谱预报,通过比较发现预报值与实测线谱频率具有较高的吻合度。

Theoretical prediction on cavitation line-spectrum frequency of underwater high speed target contra-rotating propeller

Underwater high speed target counter-rotation propeller always works at cavitation condition, the cavitation noise line-spectrum is due to the interaction between fore and aft propeller, and the interaction between the fore or aft and wake of the ship. According to the acoustic analogy equation of Goldstein and making vacuole as one part of propeller, the academic prediction of counter-rotation propeller cavitation line-spectrum frequency is presented in this paper. The far field sound pressure expression of monopole sound source is derived, and the line-spectrum prediction frequency is gained. The agreement of predicted results compared with practical data is quite satisfied.