설비공학논문집 (Korean Journal of Air-Conditioning and Refrigeration Engineering)
- 제11권2호
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- Pages.167-175
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- 1999
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- 1229-6422(pISSN)
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- 2465-7611(eISSN)
다익 송풍기의 이산 주파수 소음 저감을 위한 실험적 연구
An experimental study for reduction of B.P.F. noise level of multi-blade fan
초록
B.P.F.(Blade Passing Frequency) levels were measured with the cut-off clearance changes. The velocity inside the scroll, pressure fluctuation at cut-off region, and the scroll surface pressure distribution along the scroll from the cut-off to outlet were measured. With a certain cut-off clearance the improvement of efficiency and attenuation of B.P.F. noise level could be achieved. The measured results of pressure fluctuation and scroll surface pressure distribution showed that the secondary flow inside the scroll increased B.P.F. noise level at the cut-off region as the cut-off clearance got wide.