Investigation of aerodynamic performance of small axial flow fan coupled with deflecting ring

Abstract

Experimental and numerical investigations on the effect of deflecting rings featuring different axial lengths on aerodynamic performance of the small axial flow fan were conducted under the condition of maximum flow rate. Two deflecting rings, the semi-open type and closed type, were investigated. Aerodynamic and aeroacoustic performances have been measured in experiment, and key analysis of flow was based on computational fluid dynamics results. The numerical and experimental results show that the deflecting ring has great influence on the performance of an axial flow fan. For the semi-open-type deflecting ring, the fan has better P-Q performance and higher efficiency; pressure, vorticity, and vorticity gradient distributions on the blade surface are more uniform; and noise level of the fan is lower at wider frequency bands. For the closed-type deflecting ring, the performance curve has a convex feature; blade pressure difference between the pressure surface and the suction surface is much bigger. The result shows that better aerodynamic and aeroacoustic performances of the axial flow fan can be acquired when the semi-open-type deflecting ring is adopted.

CFD Analysis and Optimization of Effect of Shroud with Multi-outlets on Airflow Uniformity in a Frost-Free Refrigerator

“…In the field of household appliances, Wu et al (2014) studied the effects of parameters of the bell-shaped shroud on the aerodynamic performance of DC frequency conversion split-type air-conditioning units based on three-dimensional computational fluid dynamics (CFD). Huang et al (2017) used computational fluid dynamics and experimental methods to study the effects of different shroud structures on the aerodynamic performance of an axial fan at the refrigerator compressor. Hu et al (2006) used CFD to study the influence of the shroud on the aerodynamic performance of the split-unit airconditioning outdoor unit and verified that the shroud with diversion ducts can improve the aerodynamic performance.…”