浸没式喷水推进器水动力噪声的数值预报

Numerical prediction of hydrodynamic noise of submerged waterjet

为掌握浸没式喷水推进器水动力噪声的基本特征,基于点源模型和边界元方法探索该型推进器噪声的数值预报方法,并分析导管内壁面脉动压力特点以及导管对叶轮声场的屏蔽效应。结果表明:浸没式喷水推进器由于存在叶轮和导叶的相互作用,使得在导管内壁面存在较强的径向力脉动,导致静止部件声场在径向方向贡献最大;导管对旋转叶轮声场在较大范围内均存在一定的屏蔽效果,在径向方向最为显著;导管屏蔽效应导致推进器声场指向性与螺旋桨声场指向性存在较大差异。

In order to understand the characteristic of submerged waterjet hydrodynamic noise,the numerical prediction method of waterjet noise was explored by using point source model and doundary element method.The characteristics of fluctuating pressure on the inner wall of duct and the shielding effect of the duct on the acoustic field of the impeller were analyzed.The results show that the interaction between impeller and stator of submerged waterjet thruster results in strong radial force pulsation,that caused the stationary parts sound field contribution the most radially.The duct has shielding effect on the sound field of rotating impeller in a large range,and most prominent in radial.As result,there is a big difference between the sound field directivity of impeller and propeller.