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

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

DOI QR Code

Effects of Wake-Passing Orientation and Frequency on Unsteady Boundary Layer Transition on an Airfoil

주기적 통과 후류의 방향과 주파수가 익형 위 비정상 천이경계층에 미치는 영향

  • Published : 2002.05.01
Download PDF
⟨ Previous Next ⟩

Abstract

Effects of wake-passing orientation and frequency on the wake-induced boundary layer transition on a NACA0012 airfoil are investigated. The wakes are generated by rotating cylinders clockwise (CW) and counterclockwise (CCW) around the airfoil. Time- and phase-averaged streamwise mean velocities and turbulent fluctuations are measured with a single hot-wire probe. Wall skin frictions are estimated by the Computational Preston Tube Method (CPM). The pressure distribution on the airfoil is different according to the wake-passing orientation and frequency. Turbulent patches are generated in the laminar boundary layer due to the passing wake and the boundary layer becomes temporarily transitional. The transition process is significantly affected by the pressure gradient and the turbulent patches. For the receding wake, the turbulent patches propagate more rapidly than those for the approaching wake because adverse pressure gradient becomes larger. As the frequency increases, onset location of transition moles upstream and the boundary layer near the trailing edge becomes more transitional.

Keywords

References

  1. 박태춘, 전우평, 강신형, 2001a, '주기적 후류내의 익형 위 천이경계층에 관한 실험적 연구: Part I-시간평균된 유동특성,' 대한기계학회 논문집(B), 제25권, 제6호, pp. 776-785
  2. 박태춘, 전우평, 강신형, 2001b, '주기적 후류 내의 익형 위 천이경계층에 관한 실험적 연구: Part II-위상평균된 유동특성,' 대한기계학회 논문집(B), 제25권 제6호, pp. 786-798
  3. Jeon, W.-P., Park, T.-C., Kang, S.-H., 2001, 'Experimental Study of Boundary Layer Transition on an Airfoil Induced by Periodically Passing Wake,' Exps. Fluids (in print) https://doi.org/10.1007/s003480100353
  4. Dong, Y. and Cumpsty, N. A., 1990a, 'Compressor Blade Boundary Layers: Part I- Test Facility and Measurements with No Incident Wakes,' ASME J. Turbomachinery, Vol. 112, pp. 222-230 https://doi.org/10.1115/1.2927636
  5. Dong, Y. and Cumpsty, N. A., 1990b, 'Compressor Blade Boundary Layers: Part II-Measurements with Incident Wakes,' ASME J. Turbomachinery, Vol. 112, pp. 231-240 https://doi.org/10.1115/1.2927637
  6. Liu, X. and Rodi, W., 1991, 'Experiments on Transitional Boundary Layers with Wake- Induced Unsteadiness,' J. Fluid Mechanics, Vol. 231, pp. 229-256 https://doi.org/10.1017/S0022112091003385
  7. Halstead, D. E., Wisler, D. C., Okiishi, T. H., Walker, G. J., Hodson, H. P. and Shin, H., 1997a, 'Boundary Layer Development in Axial Compressors and Turbines: Part I-Composite Picture,' ASME J. Turbomachinery, Vol. 119, pp. 114-127 https://doi.org/10.1115/1.2841000
  8. Wu, X., Jacobs, R. G., Hunt, J. C. R. and Durbin, P. A., 1999, 'Simulation of Boundary Layer Transition Induced by Periodically Passing Wakes,' J. Fluid Mechanics, Vol. 398, pp. 109-153 https://doi.org/10.1017/S0022112099006205
  9. Nitsche, W., Thunker, R. and Haberland, C., 1983, 'A Computational Preston Tube Method,' Turbulent Shear Flow 4, Springer, pp. 261-276
  10. Hodson, H. P., 1985, 'Measurements of Wake-Generated Unsteadiness in the Rotor Passages of Axial Flow Turbines,' ASME J. Engineering for Gas Turbines and Power, Vol. 107, pp. 467-476 https://doi.org/10.1115/1.3239751
  11. Funazaki, K. and Koyabu, E., 1999, 'Effects of Periodic Wake Passing upon Flat-Plate Boundary Layers Experiencing Favorable and Adverse Pressure Gradients,' ASME J. Turbomachinery, Vol. 121, pp. 333-340 https://doi.org/10.1115/1.2841319
  12. Pfeil, H., Herbst, R. and Schroder, T., 1983, 'Investigation of the Laminar-Turbulent Transition of Boundary Layers Disturbed by Wakes,' ASME J. Engineering for Power, Vol. 105, pp. 130-137 https://doi.org/10.1115/1.3227373
  13. Orth, U., 1993, 'Unsteady Boundary Layer Transition in Flow Periodically Disturbed by Wakes,' ASME J. Turbomachinery, Vol. 115, pp. 707-713 https://doi.org/10.1115/1.2929306