Noise characteristics of screw mixed-flow water-jet pump
HAN Wei1,2*,GUO Wei1,XU Dandan1,LI Rennian1,2,CHEN Ran1
1. College of Energy and Power Engineering, Lanzhou University of Technology, Lanzhou, Gansu 730050, China; 2. Key Laboratory of Fluid Machinery and System, Gansu Province, Lanzhou, Gansu 730050, China
Abstract:Numerical calculations of unsteady flow in a screw mixed-flow water-jet pump were carried out based on DES turbulence model to investigate noise characteristics and noise generation mechanism in the pump under different operating conditions.The unsteady pressure pulsation on the surface of each flow component was extracted and used as sound sources, and the noise caused by the dipole source of each flow component was numerically calculated by using FEM and vibro-acoustic coupling method. The noise distribution in the external field was obtained.The noise distribution characteristics of every flow component were analyzed. The results show that the casing dipole source is the main contributor to external noise. The SPL issued from the impeller dipoleis the highest near the bladeinlet, and the unsteady pressure load on the blade surface and the rotor-stator interaction are the main reason for impeller noise. The SPL of the guide vane dipole source is the highest in the area with the maximum curvature and the inlet, the unsteady flow and rotor-stator interaction are the main cause for guide vane noise.