Journal of Mechanical Science and Technology

  • 제20권7호
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  • Pages.1077-1088
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  • 2006
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  • 1738-494X(pISSN)
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  • 1976-3824(eISSN)
대한기계학회 (The Korean Society of Mechanical Engineers)
권호 표지

Numerical Predictions of Roughness Effects on the Performance Degradation of an Axial-Turbine Stage

  • Kang Young-Seok (School of Mechanical and Aerospace Engineering, Seoul National University) ;
  • Yoo Jae-Chun (Halla Climate Control Corp.) ;
  • Kang Shin-Hyoung (Department of Mechanical and Aerospace Engineering, Seoul National University)
  • 발행 : 2006.07.01
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초록

This paper describes a numerical investigation on the performance deteriorations of a low speed, single-stage axial turbine due to use of rough blades. Numerical calculations have been carried out with a commercial CFD code, CFX-Tascflow, by using a modified wall function to implement rough surfaces on the stator vane and rotor blade. To assess the stage performance variations corresponding to 5 equivalent sand-grain roughness heights from a transition ally rough regime to a fully rough regime, stage work coefficient and total to static efficiency were chosen. Numerical results showed that both work coefficient and stage efficiency reduced as roughness height increased. Higher surface roughness induced higher blade loading both on the stator and rotor which in turn resulted in higher deviation angles and corresponding work coefficient reductions. Although, deviation angle changes were small, a simple sensitivity analysis suggested that their contributions on work coefficient reductions were substantial. Higher profile loss coefficients were predicted by higher roughness heights, especially on the suction surface of the stator and rotor. Furthermore sensitivity analysis similar to the above, suggested that additional profile loss generations due to roughness were accountable for efficiency reductions.

키워드

참고문헌

  1. AEA-Technology, 1999, 'CFX-TASCflow Theory Documentation version 2.9'
  2. Bammert, K. and Sandstede, H., 1980, 'Measurements of the Boundary Layer Development along a Turbine blade with Rough Surface,' ASME J. Turbomach., 102, pp.978-983
  3. Bammert, K. and Milsch, R., 1972, 'Boundary Layers on Rough Compressor Blades,' ASME Paper No. 72-GT-48
  4. Boyle, R. L. and Senyitko, R. G., 2003, 'Measurements and Prediction of Surface Roughness Effects on Turbine Vane Aerodynamics,' ASME paper GT2003-38580
  5. Boynton, J. L., Tabizadeh, R. and Hudson, S. T, 1993, 'Investigation of Rotor Blade Roughness Effects on Turbine Performance,' ASME J. Turbomach., 124, pp. 614-620
  6. David, C. Wilcox, 1993, 'Turbulence Modeling for CFD,' DCW Industries, Inc.
  7. Frank M. White, 1991, 'Viscous Fluid Flow,' .
  8. Guo, S. M., Jones, T. V., Lock, G. D. and Dancer, S. N., 1998, 'Computational Prediction of Heat Transfer to Gas Turbine Nozzle Guide Vanes With Roughened Surfaces,' ASME J. Turbomach., 120, pp. 343-350 https://doi.org/10.1115/1.2841412
  9. Kang, S. H., Kang, Y. S. and Han, K. H., 2003, 'Numerical Study on Blade Roughness Effect on the Performance of Turbo-machines,' IGTC2003-TS033
  10. Kind, R. J., Serjak, P. J., Abbott, M. W. P., 1998, 'Measurments and Prediciton of the Effects of Surface Roughness on Profile Losses and Deviation in a Turbine Cascade,' ASME J. Turbomach., 120, pp. 20-27 https://doi.org/10.1115/1.2841383
  11. Nikuradse, J., 1931, 'Laws For Flows In Rough Pipes,' VDI - Forchungsheft 361, Series B, Vol. 4, pp. 361
  12. Schlichting, H., 1979, 'Boundary Layer Theory,' 7th Edition, McGraw-Hill, New York
  13. Souders, D. T. and Hirt, C. W., 2002, 'Modeling Roughness Effects in Open Channel Flows,' Flow Science Technical Note (FSI-02-TN60)
  14. Yoon, Y. S., 2002, 'Turbine Experiment Equipment Design and Blades Performance Evaluation,' M.S Thesis, Seoul National University
  15. Yun, Y. I., Park, I. Y. and Song, S. J., 2004, 'Performance Degradation Due to Blade Surface Roughness in a Single-Stage Axial Turbine,' ASME Papers 2004-GT-53094