Abstract：Based on LIGHTHILL acoustic analogy theory and FW-H equation, computational fluid dynamics and computational acoustics were used to solve the internal noise of a single-blade centrifugal pump, and the sound source characteristics of the internal flow field under different flow conditions were explored. A hybrid numerical simulation method and the SST k-ω turbulence model were adopted to perform unsteady simulation of the centrifugal pump. The sound source information was exported, and acoustic calculations was performed. The internal field noise of single-blade centrifugal pumps at different flow rates was analyzed. The results show that the energy of the pressure pulsation of the single-blade centrifugal pump is mainly concentrated in the blade frequency and its harmonic frequency in the lowfrequency range. The energy of the internal noise is mainly concentrated in the low frequency band, and the energy of the noise component is higher at the blade frequency and its harmonic frequency. With the increase of the flow rate, the flow pattern of the flow channel in the volute and the impeller is gradually improved, and the secondary flow and flow separation phenomenon was reduced. It results in an obvious downward trend in low frequency harmonic noise. According to the frequency spectrum analysis of the sound power level under different flow rates, it can be found that the distribution characteristics of the pressure pulsation have a direct effect on the internal hydrodynamic noise of the single-blade centrifugal pump.
