An analysis of noise radiation characteristics of pumpjet propulsor with rear stator

To investigate the noise radiation characteristics of the rear stator pumpjet propulsor, a rod-airfoil model was used to verify the noise numerical method. A transient simulation of the research model was carried out using a block structured grid. This study analyzed the influence of the rear stator on the flow field, extracted noise data from several monitoring points around the model, and examined the noise radiation characteristics. The results show that the stator blades increase the axial velocity of the rotor wake, thereby improving the thruster′s propulsion performance. Furthermore, the stator blades balance the pressure vortex generated by the rotor, resulting in a uniform wake pressure distribution. In terms of the overall sound field directional distribution, rotor noise in the axial direction has the most significant impact, while duct noise in the small-scale radial direction also notably affects the overall noise. The stator noise contributes the least to the overall noise. As the distance from the source increases, the directivity of the low-pressure zone in the acoustic field narrows from 120° and 240° at the leading edge toward the center, eventually forming an “∞” shape overall. In the axial direction, low-frequency noise attenuates the fastest, and the attenuation rate increases with distance. Conversely, in the radial direction, the decay rate of low-frequency noise changes is not significant. © 2024 Editorial Board of Journal of Harbin Engineering. All rights reserved.