Abstract: An indirect method based on CFD and Lighthill sound analogy theory was adopted to solve the acoustic field of volute in centrifugal pumps for the complexity of the acoustic boundary conditions and high requirement of computational resources of the direct method. The DES method and S-A model were used to process threedimensional unsteady simulation. Dipole is the main noise source in pumps and the datum of pressure fluctuation were extracted from the CFD results as dipole input into SYSNOISE5.6 as the initial conditions. In acoustic simulation, the distribution graphs about dipole source and sound pressure can be got using DBEM. The results show that the distribution of the acoustic source which directly associate to the pressure fluctuation of the volute face generally aggregate at cutwater with the same frequency characteristic. Field sound pressure and dipole source do not have simple linear relationship and the strongest radiation intensity appears at blade passing frequency. Pipeline method applied in flow induced noise measurement is feasible and the flow rate is one of the major factors in acoustic radiation.
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