基于大涡模拟的轮缘侧推器和常规侧推器非空泡噪声对比分析

Comparative Analysis of Non-cavitation Noise between Wheel Rim Thruster and Conventional Thruster Based on Large Eddy Simulation

提出了基于大涡模拟(LES)方法与FW-H声学模型相结合的侧推器噪声仿真方法,通过导管桨敞水性能试验值与仿真值的对比,以及侧推器流场基频和各次谐波计算值与仿真值的对比,验证了基于LES方法的侧推器流噪声仿真方法的准确性。在此基础上,研究了轮缘侧推器和常规侧推器在非均匀来流时的流场分布,获取了侧推器桨叶等水力部件的声压时域和频域。结果表明:侧推器产生的流噪声主要为低频噪声,轮缘侧推器横向和径向总声压级分别比常规侧推器小3 dB和10 dB左右;侧推器噪声分布主要呈现偶极子特性,桨叶横向总声压级高于径向。

A noise simulation method of the thruster of a new type of ship’s shaft-less wheel flange is proposed based on the combination of large eddy simulation(LES)and FW-H acoustic model.Comparison of the open water performance of a ducted propeller between the experiment and the simulation verifies the accuracy of the simulation.Flow field distribution of the shaft-less thruster and the conventional thruster in the non-uniform flow is compared,and sound pressure of the thruster blades and other hydraulic components is obtained in both time domain and frequency domain.The results show that the flow noise generated by the thruster is mainly low-frequency one.Total lateral sound pressure level of the shaft-less thruster is about 3 dB lower than that of the conventional thruster,and total longitudinal sound pressure level of the shaft-less thruster is about 10 dB lower than that of the conventional thruster.Noise distribution of the thruster mainly presents dipole characteristics,and total sound pressure level in the transverse direction of the blade is higher than that in the radial direction.