Investigations regarding the relation of noise performance for centrifugal pump operating in pump and turbine modes continue to be inadequate. This paper presents a series of comparisons of flow-induced noise for both operation modes. The interior flow-borne noise and structure modal were verified through experiments. The flow-borne noise was calculated by the acoustic boundary element method (ABEM), and the flow-induced structure noise was obtained by the coupled acoustic boundary element method (ABEM)/structure finite element method (SFEM). The results show that in pump mode, the pressure fluctuation in the volute is comparable to that in the outlet pipe, but in turbine mode, the pressure fluctuation in the impeller is comparable to that in the draft tube. The main frequency of interior flow-borne noise lies at blade passing frequency (BPF) and it shifts to the 9th BPF for interior flow-induced structure noise. The peak values at horizontal plane appear at the 5th BPF, and at axial plane, they get the highest sound pressure level (SPL) at the 8th BPF. Comparing with interior noise, the SPL of exterior flow-induced structure noise is incredibly small. At the 5th BPF, the pump body, cover and suspension show higher SPL in both modes. The outer walls of turbine generate relatively larger SPL than those of the pump.%离心泵在泵与透平运行工况下噪声性能关联关系的研究还不充分,本文对两种工况下的流体诱发噪声特性进行对比研究.在试验验证内部流动噪声和结构模态准确性的基础上,采用声边界元法(ABEM)计算流动噪声,采用声边界元/结构有限元耦合法(ABEM/SFEM)计算流激结构声.结果表明,在泵工况下,蜗壳内的压力脉动水平与出口管相当;但在透平工况下,叶轮内的压力脉动水平与尾水管相当.内场流动噪声的主频为叶频,而内场流激结构声的主频为9倍叶频.对于外场噪声,水平面上的噪声峰值出现在5倍叶频,而轴面上的峰值出现在8倍叶频.与内场噪声相比,外流流激结构声的声压级相当小.对于两种工况,泵体、泵盖和悬架在5倍叶频处都辐射出较高的声压级;而透平工况下的外壁面辐射出的声压级相对较大.
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