Transactions of the Korean Society of Mechanical Engineers B (대한기계학회논문집B)

The Korean Society of Mechanical Engineers (대한기계학회)
권호 표지
DOI QR코드

DOI QR Code

Structure of Tip Leakage Flow in a Forward-Swept Axial-Flow Fan

전향 축류형 홴에서의 익단 누설 유동 구조

  • 이공희 (포항공과대학교 대학원 기계공학과) ;
  • 명환주 (LG전자 DA연구소) ;
  • 백제현 (포항공과대학교 기계공학과)
  • Published : 2003.07.01
Download PDF
⟨ Previous Next ⟩

Abstract

The experiment using three-dimensional laser Dopperr velocimetery (LDV) measurements and the computation using the Reynolds stress model of the commercial code, FLUENT, were conducted to give a clear understanding on the structure of tip leakage flow in a forward-swept axial-flow fan operating at the maximum efficiency condition. The tip leakage vortex was generated near the position of the minimum wall static pressure, which was located at approximately 12% chord downstream from the leading edge of blade suction side, and developed along the centerline of the pressure trough within the blade passages. A reverse flow between the blade tip region and the casing, induced by tip leakage vortex, acted as a blockage on the through-flow. As a result, high momentum flux was observed below the tip leakage vortex. As the tip leakage vortex proceeded to the aft part of the blade passage, the strength of tip leakage vortex decreased due to the strong interaction with the through-flow and casing boundary layer, and the diffusion of tip leakage vortex caused by high turbulence. In comparison with LDV measurement data, the computed results predicted the complex viscous flow patterns inside the tip region, including the locus of tip leakage vortex center, in a reliable level.

Keywords

References

  1. Morris, S. C., Good, J. J. and Foss, J. F., 1998 'Velocity Measurements in the Wake of an Automotive Cooling Fan,' Exp. Thermal Fluid Sci., Vol.17, pp. 100-106 https://doi.org/10.1016/S0894-1777(97)10054-1
  2. Lauchle, G. C., MacGillivray, J. R. and Swanson, D. C., 1997, 'Active Control of Axial-Flow Fan Noise,' J. Acoust. Soc. America, Vol.101, pp.341-349 https://doi.org/10.1121/1.417979
  3. Choi, J. H. and Kim, K. Y., 2000, 'Assessment of Numerical Optimization Algorithms in Design of Low-Noise Axial-Flow Fan,' Trans. KSME (B), Vol.24, No.10, pp.1335-1342
  4. Kim, J. K. and Kang, S. H., 2000, 'Performance and Flow Characteristics of a Forward Swept Propeller Fan,' Trans. KSME (B), Vol.24, No.1, pp.75-84
  5. Rains, D. A., 1954, 'Tip Clearance Flows in Axial Flow Compressors and Pumps,' Hydrodyn. Mech. Eng. Lab., California Institute of Technology, Report No.5
  6. Inoue, M. and Kuroumaru, M., 1989, 'Structure of Tip-Clearance Flow in an Isolated Axial Compressor Rotor,' ASME J. Turbomachery, Vol.111, pp.250-256 https://doi.org/10.1115/1.3262263
  7. Lakshminarayana, B. and Pouagare, M., 1982, 'Three-Dimensional Flow Field in the Tip Region of a Compressor Rotor Passage - Part I: Mean Velocity Profiles and Annulus Wall Boundary Layer,' ASME J. Eng. Power, Vol.104, pp.761-771
  8. Lakshminarayana, B., Davino, R. and Pouagare, M., 1982, 'Three-Dimensional Flow Field in the Tip Region of a Compressor Rotor Passage - Part 2: Turbulence Properties,' ASME J. Eng. Power, Vol.104, pp.772-781 https://doi.org/10.1115/1.3227343
  9. Puterbaugh, S. L. and Brendel, M., 1997, 'Tip Clearance Flow-Shock Interaction in a Transonic Compressor Rotor,' J. Prop. Power, Vol.13, pp.24-30 https://doi.org/10.2514/2.5146
  10. Sieverding, C. H., 'Secondary and Tip-Clearance Flows in Axial Turbines,' 'Von Karman Inst. Lecture series, LS 1997-01
  11. FLUENT, 1998, User's Guide Ver.5, FLUENT Inc.
  12. Synder, P. K., Orloff, K. L. and Reinath, M. S., 'Reduction of Flow Measurement Uncertainties in Laser Velocimeters with Nonorthogonal Channels,' AIAA J., Vol.22, No.8, pp.1115-1123 https://doi.org/10.2514/3.8746
  13. Lee, G. H. and Baek, J. H., 2002, 'A Numerical Study on the Structure of Tip Clearance Flow in a Highly Forward-Swept Axial-Flow Fan,' ASME-European Joint Conf. on 6th Int. Symp. on Advances in Num. Modeling of Aerodyn. and Hydrodyn. in Turbomachinery, Montreal, Canada
  14. Lee, G. H. and Baek, J. H., 2002, 'Numerical Analysis of Internal Flow through Impeller for Matching Turbocharger,' Final Report, KIMM
  15. Durbin, P. A., 1996, 'On the ${\kappa}$-3 Stagnation Point Anomaly,' Int J. Heat Fluid Flow, Vol.17, pp.89-90 https://doi.org/10.1016/0142-727X(95)00073-Y
  16. GAMBIT, 1998, User's Guide Ver.1, FLUENT Inc.
  17. Lighthill, M. J., 1952, 'On Sound Generated Aerodynamically: 1. General theory,' Proc. Royal Society, A211, pp.564-587 https://doi.org/10.1098/rspa.1952.0060