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http://dx.doi.org/10.3795/KSME-B.2005.29.3.322

Flow Characteristics of Wake Flow with Relation to a Tip Leakage Vortex at Different Flow Rates in an Axial Flow Fan  

Kim Kwang-Yong (인하대학교 기계공학부)
Jang Choon-Man (한국건설기술연구원)
Publication Information
Transactions of the Korean Society of Mechanical Engineers B / v.29, no.3, 2005 , pp. 322-329 More about this Journal
Abstract
The flow characteristics in the blade passage and in the wake region of a low speed axial flow fan have been investigated by experimental analysis using a rotating hot-wire sensor for design and off-design operating conditions. The results show that the tip leakage vortex is moved upstream when flow rate is decreased, thus disturbing the formation of wake flow near the rotor tip. The tip leakage vortex interfaces with blade pressure surface, and results in high velocity fluctuation near the pressure surface. From axial velocity distributions downstream of the fan rotor, large axial velocity decay near the rotor tip is observed at near stall condition, which results in large blockage compared to that at the design condition. Although the wake flow downstream of the rotor blade is clearly measured at all operating conditions, the trough of the high velocity fluctuation due to Karmann vortex street in the wake flow is mainly observed at a higher flow condition than the design flow rate.
Keywords
Axial Flow Fan; Rotating Hot-Wire Sensor; Tip Leakage Vortex; Wake Flow;
Citations & Related Records
Times Cited By KSCI : 2  (Citation Analysis)
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