Abstract:
In order to study the effect of the guide vane on the internal and external acoustic field of centrifugal pump for hydraulic turbine level, a single-stage, single-suction centrifugal pump with a specific rotational speed of ns=84.5 is reversed for turbine level as the research object. ANSYS Fluent numerical simulation and acoustic boundary element/finite element (ABEM/FEM) method are used to calculate the flow field and sound field of the centrifugal pump as a hydraulic turbine, respectively. The results show that: in the internal sound field, the addition of guide vane has a greater impact on the sound pressure level of the inlet, in the first order of the lobe frequency, the guide vane has a greater impact on the sound pressure level of the inlet, and the reduction of the sound pressure level in the optimal working condition is more obvious, the value of which is 1.2 dB; the impact of the sound pressure level at the outlet is smaller, and the reduction in the reduction of the sound pressure level is gradually decreasing with the increase of the flow rate. In terms of the external sound field, the maximum sound pressure level occurs near the inlet, outlet, tongue and base, the sound pressure level cloud shows dipole source characteristics, and the reduction of the sound pressure level is more obvious under the optimal working condition; after adding the guide vane, the plane radiation value of the external sound field is significantly reduced compared with the original model in the high sound pressure level area. The above study can provide some theoretical references for the reduction of hydraulic turbine noise in the future.