以某型七叶大侧斜螺旋桨为研究对象，视螺旋桨为弹性体，采用计算流体力学(Computational Fluid Dynam-ics，CFD)耦合有限元法(Finite Element Method，FEM)的双向流固耦合方法，计算螺旋桨水动力性能。通过现有试验数据及相关文献验证该数值方法的准确性。并基于时域下桨叶表面的脉动压力作为旋转偶极子声源，通过傅里叶变换及声学有限元软件LMS Virtual。Lab计算分析七叶大侧斜弹性桨的非空泡噪声特性。结果表明，在5～1000 Hz频段内，弹性桨的辐射声压级大于刚性桨。桨叶低阶弹性振动容易被激发，产生共振。针对偶极子声源，桨叶轴向平面内，远场的声压指向性主要为"∞"形分布，并且轴向的声压级远大于盘面方向，更容易被敌方声纳探测。近水面会影响螺旋桨辐射声压级的大小，越接近水面，声压幅值越小，这一现象在远场点处更显著。此外，螺旋桨轴向两端的声压指向性受近水面影响呈现不对称分布。
Non-cavitating Noise Characteristics of Large Skew Elastic Propellers
A seven-blade highly skewed propeller was taken as the research object.Regarding the propeller as an elas-tic body,its hydrodynamic performance was calculated by the two-way fluid-solid coupling method of computational fluid dynamics (CFD) and finite element method (FEM).The accuracy of the numerical method was verified by the existing exper-imental data and the related literature.With the fluctuating pressure on the blade surface in the time domain as the rotating di-pole sound source,the non-cavitating noise characteristics of the seven-blade highly skewed elastic propeller were calculated and analyzed by Fourier transform and acoustic finite element software LMS Virtual.Lab.The results show that the radiation sound pressure level of the elastic propeller is greater than that of the rigid propeller in the 5-1000 Hz frequency band.The low-order elastic vibration of the blade is easily excited to produce resonance.For the dipole source,in the axial plane of the blade,the sound pressure directivity in the far field is mainly in-shaped distribution,and the axial sound pressure level is much larger than that in the disk direction,which is therefore easier to be detected by enemy sonar.The near-surface situa-tion will affect the size of the propeller radiated sound pressure level.The closer to the surface,the smaller the sound pres-sure amplitude is.This phenomenon is more pronounced at the far field point.In addition,the sound pressure directivity at both ends of the propeller is asymmetrically distributed due to the influence of the near surface situation.
acousticsnon-cavitation noiseseven-blade large skew elastic propellertwo-way fluid-structure interactiondipole sound source
万方数据
维普
