摘要
为研究螺旋桨低频空化噪声线谱的结构特征,考虑了桨叶的非均匀性和空化过程的非严格周期性,改进了螺旋桨空化过程模型,用统计方法求解了空化噪声的平均功率谱.分析了典型的空化谱特征及其在舰船航行状态不稳定和存在近场干涉时的变化情况.结果表明:典型的螺旋桨低频空化噪声线谱存在能反映叶片数的成组结构;舰船航行状态不稳定时,空化过程的周期性较弱,谐波较少;声源与接收器距离较近以及双车螺旋桨是常见的近场干涉情况,此时,线谱谐波结构发生变化.航行状态不稳定及近场干涉情况下线谱谐波结构都难以反映正确的叶片数特征.
It should be possible to determine what type of propeller is being used from the structural features of the low frequency line spectrum of the propeller＇s cavitation noise.In order to make this possible,it was necessary to improve the model for cavitation noise of propellers,accommodating non-equality of the blades and the non-strict periodicity of the cavitation process.In addition,the mean power-spectrum of propeller cavitation noise was derived.Typical structural features of the cavitation spectrum were discussed,including times when the ship encounters large waves or near field interference exists.The results showed that typical low frequency line spectrum structures could indicate the number of blades.However,when the ship encountered large waves,there were decreased periodicity in the cavitation process and fewer harmonics in the line spectrum.The harmonic structure varied more when near field interference existed.It was therefore harder to determine the correct number of blades when the ship was in large waves or there was near field interference.
出处
《哈尔滨工程大学学报》
EI
CAS
CSCD
北大核心
2010年第7期837-841,共5页
Journal of Harbin Engineering University
关键词
螺旋桨空化过程
空化噪声低频线谱
非严格周期性
近场干涉
process of propeller cavitation
low frequency line spectrum of cavatition noise
non-strict periodicity
near field interference
