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

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

DOI QR Code

2-Dimensional Film Cooling Characteristics with the Height Variation of a Stepped Slot Exit

계단형 슬롯출구의 높낮이 변화에 따른 2차원 막냉각 특성

  • 손창호 (울산대학교 기계자동차공학부) ;
  • 김태묵 (울산대학교 대학원 기계자동차공학부) ;
  • 이근식 (울산대학교 기계자동차공학부)
  • Published : 2005.01.01
Download PDF
⟨ Previous Next ⟩

Abstract

Film cooling characteristics has been examined numerically for the height variation of a stepped slot exit. In this study, the upstream wall height of the stepped slot exit varies from -2d (d = slot width) to 3d, blowing ratio ranges from 0.5 to 3, and injection angles are $15^{\circ},\;30^{\circ},\;and\;45^{\circ}$. The results showed that film cooling performance was mainly subjected to the magnitude of recirculation region near the downstream-side slot exit as well as the magnitude and the distribution region of turbulent kinetic energy due to the local velocity and momentum differences between the coolant and the main flow near the slot exit. The up-1d type slot at higher blowing ratios over 2 and the flat type slot at lower blowing ratios below 1 have the best film cooling performances, in case of the injection angles of $30^{\circ},\;and\;45^{\circ}$, respectively. Compared with the other injection angles, in case of the injection angles of $15^{\circ}$, the best film cooling performances was shown in even a higher upstream wall (up-3d) at higher blowing ratio like 3 by the gradual reduction of the coolant velocity which minimizes the local velocity differences between the coolant and the main flow near the slot exit.

Keywords

References

  1. Goldstein, R. J., 1971, 'Film Cooling,' Advances in Heat Transfer, pp. 321-379
  2. Cho, H. H., 2000, 'Flow and Heat Transfer Characteristics in Film Cooling,' KSME Spring Annual Meeting 2000 on Fluid Engineering, pp. 61-79
  3. Lee, H.-W., Park, J. J. and Lee, J. S., 2000, 'Flow Visualization and Film Cooling Effectiveness Measurement Around Shaped Holes with Compound Angle,' Recent Advances in Transport Phenomena (12th ISTP), Elsevier, pp. 45-50
  4. Son, C. H., Lee, G. S., Won, Y. H., Rho, S. M. and Lee, J. C., 2001, 'A Study on the Combination of Blowing Ratio and Injection Angle in 2-Dimensional Film Cooling,' Proc. KSME 2001 Spring Annual Meeting (D), Jeju, Korea, pp. 553-558
  5. Rhee, D. H., Kim, B. and Cho, H. H., 1999, 'Characteristics of Heat/Mass Transfer Around a Shaped Film Cooling Hole,' Trans. of the KSME (B), Vol. 23, No.5, pp. 577-586
  6. Kim, Y. B., Rhee, D. H., Lee, Y. S. and Cho, H. H., 2004, 'The Effects of Staggered Rows of Rectangular Shaped Holes on Film Cooling,' Trans. of the KSME (B), Vol. 28, No.3, pp. 304-314 https://doi.org/10.3795/KSME-B.2004.28.3.304
  7. Rho, S. M., Son, C. H. and Lee, G. S., 2001, 'Film Cooling Characteristics with Sunk or Lifted Upstream Wall,' Proc. KSME 2001 Spring Annual Meeting (D), Jeju, Korea, pp. 377-381
  8. Shih, T.-H., Liou, W. W., Shabbir, A. and Zhu, J., 1995, 'A New $k-{\varepsilon}$ Eddy-Viscosity Model for High Reynolds Number Turbulent Flows - Model Development and Validation,' Computers Fluids, Vol. 24, No.3, pp. 227-238 https://doi.org/10.1016/0045-7930(94)00032-T
  9. Yang, H. C., Ryou, H. S. and Lim, J. H., 1997, 'A Study of Applicability of a RNG $k-{\varepsilon}$ Model,' Trans. of the KSME (B), Vol. 21, No. 21, pp. 1149-1164
  10. Kim, J., Kline, S. J. and Johnston, J. P., 1980, 'Investigation of a Reattaching Turbulent Shear Layer : Flow over a 'Backward-Facing Step,' ASME J. of Fluids Engineering, Vol. 102, pp. 302-308, September https://doi.org/10.1115/1.3240686
  11. Mikhail, R., Chu, V. H. and Savage, S. B., 1975, 'The Reattachment of a Two-Dimensional Turbulent Jet in a Confined Cross Flow,' Pro. 16th IAHR Congress, Sao Paulo, Vol. 3, pp. 414-419
  12. Rodi, W., 1984, Turbulence Models and Their Application in Hydraulics, pp. 66-67

Cited by

  1. Design and Analysis of a Radial Turbine for Ocean Thermal Energy Conversion vol.39, pp.3, 2015, https://doi.org/10.3795/KSME-B.2015.39.3.207