Abstract
Miniature drainage pumps with a radial blade are widely used in situations with critical constant head and low noise requests, but the stable operation state is often broken up by the entraining gas. In order to explore the internal flow characteristics under gas–liquid two phase flow, pump performance and emitted noise measurements were processed under different working conditions. Three-dimensional numerical calculations based on the Euler inhomogeneous model and obtained experimental boundaries were carried out under different inlet air void fractions (IAVFs). A hybrid numerical method was proposed to obtain the flow-induced emitted noise characteristics. The results show there is little influence on pump characteristics when the IAVF is less than 1%. The pump head slope degradation was found to increase with air content. The bubbles adhere to the impeller hub on the blade’s suction side and spread to the periphery with a big IAVF, leading to unstable operation. It is obvious that vortices appear inside the impeller flow passage as IAVF reaches 6.5%. The two-phase flow pattern has a small effect on the characteristic frequency distribution of pressure fluctuation and emitted noise, but the corresponding pulsation intensity and noise level will increase. The study could provide some reference for low noise design of the drainage pump.
Highlights
Pumps are classified as general machinery with varied applications [1,2,3]
The two-phase flow pattern has a small effect on the characteristic frequency distribution of pressure fluctuation and emitted noise, but the corresponding pulsation intensity and noise level will increase
Confirmed with the pressure pulsation analysis above, it is known that this discrete frequency is caused by the rotor stator interaction between the impeller and the water chamber
Summary
Pumps are classified as general machinery with varied applications [1,2,3]. In addition to energy saving and emission reduction, pumps attract attention in terms of vibration and noise reduction [4,5]. Mini pumps with radial vane impellers are widely used in many fields such as electronic industries, blood pumps for medical industries, aerospace industries, and in some home appliances [6,7]. These pumps are known as mini-pumps because their sizes are smaller than 50 mm. Drainage pumps for home appliances such as drum type washing machines are mini pumps that consist of a synchronous motor with a splined shaft and a radial impeller connected with the splined shaft and the pressure chamber [8,9]. It is significant to study gas–liquid two-phase flow behavior and the relationship to pump performance and flow induced noise characteristics of radial blade pumps
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
