离心泵作透平倾斜叶片主动降噪

为降低离心泵作透平流体诱发的内外场噪声,从同相位脉动水动力作用面积与辐射噪声的关系出发,建立了叶片倾斜角度关系式,提出了在保证性能前提下倾斜叶片的主动控制降噪方法.利用透平实验平台,对2组不同倾斜角度的透平进行了水力性能、内场噪声实验;在验证壳体有限元模型的基础上,基于有限元/自动匹配层进行了外场噪声数值研究.结果表明:倾斜叶片可以保持离心泵作透平的原有水力性能,大流量工况效率最高增加1.09个百分点;同时能够降低整体频段的总声能,内场总声压级降低0.07%~3.02%,外场总声功率级大流量工况降幅最大,降低约11.97%;内外场主要频率处的声压级也得到了不同程度的降低.

Noise Reduction by Actively Leaning Blades in Centrifugal Pump as Turbine

Abstract： To reduce the fluid induced interior/exterior noise in centrifugal pump as turbine (PAT), from the relation between in phase hydrodynamic action and radiated noise, the leaned angle formula of blade in ideal condition was derived, and the noise reduction active control approach was proposed, without affecting the hydraulic performance. The hydraulic performance and interior noise of two types of PATs were compared based on the experiments. After verifying the finite element model of the casing structure, the finite element method/automatically matched layer (FEM/AML) method was used to reduce the exterior noise. The results show that the leaned blade can keep the original hydraulic performance of PAT and reduce the peak value at fundamental frequency and the total sound energy. The efficiency at larger flow rates can be mostly improved by 1.09 percentage point, the A weighted sound pressure level (OASPL) of interior noise is basically reduced by 0.07% to 3.02%, and the overall sound power of exterior noise is approximately reduced by 11.97% at 110 m3/h.