Abstract
The aerodynamic noise and the wake flow field in a cooling fan under actual operating conditions are studied with and without winglets on the fan blades. In order to understand the influence of the winglet, the aerodynamic noise and the wake velocity distribution are measured. The results indicated that overall noise level decreased and the noise spectrum was changed in a low frequency range when the winglet was installed. It was found from the flow visualization and PIV measurement that the influence of the winglet appeared in the traces of the tip vortices and the magnitude of vorticity was reduced in the near wake region, which suggest the observed reduction in aerodynamic noise
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References
Cai, W X, Shiomi, N., Sasaki, K., Kaneko, K. and Setoguchi, T, Visualization of Tip Vortex Flow in an Open Axial Fan by EFD, Journal of Visualization, 5-3 (2002), 293–300.
C. P. van Dam, Natural Laminar Flow Airfoil Design Considerations for Winglets on Low-Speed Airplanes, NASA Contract Report, NASA-CR-3853, (1984), 1–28.
Kobayashi, T et al., Handbook of Particle Image Velocimetry (First edition), (2002), 151–162, Morikita, Tokyo(in Japanese).
Nashimoto, A, Fujisawa, N., Kimura, E. and Akuto, T, Visualization of Surface Flow over a Blade of Rotating Machinery by Oil-Film Technique and Measurement of Shear Stress Distribution by Image Analysis, Journal of The Visualization Society of Japan, 20–79 (2000), 56–61 (in Japanese).
Tomimatsu, S., Fujisawa, N. and Hosokawa, A, Measurement of Aerodynamic Noise and Unsteady Flow around a Symmetrical Airfoil, Journal of Visualization, 5-4 (2002), 381–388.
Adachi, I. et al., JSME Mechanical Engineers’ Handbook; Applications; Fluid Mechinery (First edition), (1997), 26–27, Maruzen, Tokyo (in Japanese).
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Atsushi Nashimoto: After graduating from Kiryu technical high school in 1972, he joined Mitsuba Corporation in 1972 working in the Production Engineering Department from 1972 to 1978, and in the Research Department from 1978 to 1996. Since 1996, he has been engaged in the Technical Development Department and working in the field of flowvisualization of rotating machinery. Now he is a PhD. student of Niigata University.
Nobuyuki Fujisawa: After graduating from Tohoku University (D.E. 1983), he joined Gunma University in 1983 and worked as an associate professor in 1991. Since 1997, he has been a professor of Niigata University and is continuing research on the visualization and non-intrusive measurement technique of velocity, temperature and shear stress in mechanical engineering.
Tsuneo Akuto: After graduating from Keio University (MS.) in March 1971, he joined Japan INS. He later joined Mitsuba Corporation in Angust 1971, working in the Production Engineering Department from 1971 to 1972, Quality Control Department from 1972 to 1975 and Research Department from 1975 to 1994. Since 1994, he has been engaged in management of the Development Departments.
Yuichi Nagase: After graduating from Meiji University in 1976, he joined Mitsuba Corporation and worked in the Quality Control Department from 1976 to 1987, Experimental Department from 1987 to 1992 and Electronic Engineering Department from 1992 to 1998. Since 1998, he has been engaged in management of the Technical Development Department.
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Nashimoto, A., Fujisawa, N., Akuto, T. et al. Measurements of aerodynamic noise and wake flow field in a cooling fan with winglets. J Vis 7, 85–92 (2004). https://doi.org/10.1007/BF03181488
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DOI: https://doi.org/10.1007/BF03181488