Browse > Article
http://dx.doi.org/10.3795/KSME-B.2004.28.2.181

Frequency Characteristics of Fluctuating Velocity According to Flow Rates in a Tip Leakage Vortex and a Wake Flow in an Axial Flow Fan  

Jang, Choon-Man (인하대학교 기계공학부)
Kim, Kwang-Yong (인하대학교 기계공학부)
Fukano, Tohru (일본 큐슈대학교 기계과학부문)
Publication Information
Transactions of the Korean Society of Mechanical Engineers B / v.28, no.2, 2004 , pp. 181-188 More about this Journal
Abstract
The frequency characteristics in an axial flow fan operating at a design and three off-design operating conditions have been investigated by measuring the velocity fluctuation of a tip leakage vortex and a wake flow. Two hot-wire probe sensors rotating with the fan rotor. a fixed and a moving ones, were introduced to obtain a cross-correlation coefficient between two sensors as well as the fluctuating velocity. The results show that the spectral peaks due to the fluctuating velocity near the rotor tip are mainly observed in the reverse flow region of higher flow rates than those in the peak pressure operating condition. However, no peak frequency presents near the rotor tip for near stall condition. Detailed wake flow just downstream of the rotor blade was also measured by the rotating hot-wire sensor. The peak frequency of a high velocity fluctuation due to Karman vortex shedding in the wake region is mainly observed at the higher flow rate condition than that in the design point.
Keywords
Rotating Hot-Wire Probe; Cross-Correlation; Tip Leakage Vortex; Wake Flow; Frequency; Axial Flow Fan;
Citations & Related Records
Times Cited By KSCI : 2  (Citation Analysis)
연도 인용수 순위
1 Kameier, F. and Neise, W., 1997, 'Experimental Study of Tip Clearance Losses and Noise in Axial Turbomachines and Their Reduction,' Trans. of ASME, J. Turbomach., Vol. 119, pp. 460-471   DOI
2 Fukano, T., Saruwatari, H., Hayashi, H., Isobe, H., and Fukuhara, M., 1995, 'Periodic Velocity Fluctuation in the Near Wake of a Rotating Flat-Plate Blade and Their Role in the Generation of Broadband Noise,' J. Sound Vib., Vol. 181, pp. 53-70   DOI   ScienceOn
3 Murthy, K. N. S., and Lakshminarayana, B., 1986, 'Laser Doppler Velocimeter Measurement in the Tip Region of a Compressor Rotor,' AIAA J., Vol. 24, No. 5, pp. 807-814   DOI   ScienceOn
4 Inoue, M., and Kuroumaru, M., 1989, 'Structure of Tip Clearance Flow in an Isolated Axial Compressor Rotor,' ASME J. Turbomachin., Vol. 111, pp. 250-256   DOI
5 Lakshminarayana, B., Zaccaria, M., and Marathe, B., 1995, 'The Structure of Tip Clearance Flow in Axial Flow Compressors,' ASME J. Turbomachin., Vol. 117, pp. 336-347   DOI
6 Ro, S. H. and Cho, K. R., 1998, 'Numerical Analysis on the Blade Tip Clearance Flow in the Axial Rotor - The Variation of Leakage Vortex with Tip Clearance,' Trans. of KSME (B), Vol. 22, No. 3, pp. 336-345
7 Jang, C.-M. and Kim, K. Y., 2003, 'Flow Measurements and Performance Analysis Using a 5-Hole Pitot Tube and a Rotating Hot-Wire Probe in an Axial Flow Fan,' Trans. of KSME (B), Vol. 27, No. 12, pp. 1750-1757   과학기술학회마을   DOI
8 Inoue, M., and Furukawa, M., 2002, 'Physics of Tip Clearance Flow in Turbomachinery,' ASME FEDSM 31184, pp. 1-13
9 Jang, C. M., Ogata, N., Furukawa, M., and Fukano, T., 2002, 'Characteristics of Three-Dimensional Flow Field and Velocity Fluctuation Near the Rotor Tip in an Axial Flow Fan (Relation to the Noise Generation),' Trans. of JSME (B), Vol. 68, No. 673, pp. 2460-2466   DOI