艇后大侧斜螺旋桨非定常空化及噪声性能研究

Study on Unsteady Cavitation and Noise Performance of a High Skewed Propeller Behind the SUBOFF Boat

结合数值和试验方法,对艇后七叶大侧斜螺旋桨进行空化性能及空化噪声分析.采用雷诺平均(RANS)方法和Ffows Williams-Hawkings声学类比方程混合的计算方法,结合SST k-ω湍流模型和Schnerr-Sauer空化模型,研究了艇后七叶螺旋桨的非定常空化脉动压力、推力系数、速度分布及空化形态演变过程,并将数值结果与试验结果进行比较验证.基于艇后螺旋桨空化噪声的数值仿真,分析不同空化数下各阶压力脉动幅值、噪声功率谱、频率普.结果表明:随着空化数的减小,脉动压力波动峰值减小,桨叶无明显空化时,噪声高幅值主要集中在低频段,空化发生时,高频段噪声的声压级会明显增大,声功率级增大60 dB,而低频段的噪声随着空化的发展而增加,空化完全发展时,所有频段噪声一起增大到更高水平.

Combined with numerical and experimental methods,the cavitation performance and cavitation noise of the seven-blade large lateral oblique propeller behind the boat were analyzed.The unsteady cavitation fluctuating pressure,thrust coefficient,velocity distribution and evolution process of cavitation morphology of the seven-blade propeller behind the boat were studied by using the hybrid calculation method of RANS method and Ffows Williams-Hawkings acoustic analogy equation,combined with SST turbulence model and Schnerr-Sauer cavitation model,and the numerical results were compared with the experimental results.Based on the numerical simulation of cavitation noise of propeller behind the boat,the amplitude,noise power spectrum and frequency spectrum of pressure pulsation of each order under different cavitation numbers were analyzed.The results show that with the decrease of cavitation number,the peak value of fluctuating pressure decreases,and there is no obvious cavitation in the blade.The high amplitude of noise is mainly concentrated in low frequency band.When cavitation occurs,the sound pressure level of high frequency band noise will increase obviously,and the sound power level will increase by 60 dB.However,the noise in low frequency band increases with the development of cavitation,and when cavitation develops completely,the noise in all frequency bands increases to a higher level together.