Numerical Simulation and Analysis of the Cavitation Noise Characteristics of an IMP Propulsor

Abstract The objective of this study is to ascertain the cavitation noise characteristics of an integrated motor pump-jet (IMP) propulsor. The far-field cavitation radiation noise of the propulsor is analysed using computational fluid dynamics and acoustic coupling methods. The results indicate that in comparison with non-cavitation noise, the IMP propulsor generates an increased level of noise as a consequence of cavitation. Strong correlation is observed between the variables of cavitation volume pulsation and radiation noise. The initial rise in the overall sound pressure level of the radiation noise inside the propulsor is followed by a gradual increase as the degree of cavitation deepens. Concurrently, the total noise increases, while the significance of the blade frequency weakens. Variations in the blade tip gap have a pronounced influence on the intensity of cavitation noise. Under identical conditions in terms of the axial gap, the cavitation noise attains its minimum level when the radial gap is set to 3 mm. Conversely, an increase in the axial gap results in a corresponding rise in cavitation noise when the radial gap remains constant. The findings of this study will provide valuable insights for the noise control of IMP propulsors.