THERMAL SCIENCE

International Scientific Journal

IMPACT OF V-SHAPED INTERRUPTED RIBS IN CROSS-FLOW CHANNELS ON FILM COOLING

ABSTRACT
This study primarily investigates the enhanced heat transfer of V-shaped ribs with¬in an internal cross-flow channel and their impact on external film cooling per¬formance. The aim is to assess the advantages of V-shaped ribs in the cooling of gas turbine blades. The research specifically discusses the internal heat transfer efficiency of smooth channels, channels with V-shaped ribs, and channels with intermittently placed V-shaped ribs at a blowing ratio, M, of 0.5 and three different Reynolds numbers. The results indicate that the vortices generated by the coolant passing through the positive V-shaped ribs and intermittently placed V-shaped ribs effectively impinge on the upper and lower surfaces, thereby enhancing heat trans¬fer performance. Regarding film cooling, under low Reynolds number conditions, the film cooling efficiency of the positive V-shaped ribs is 9-20% higher than that of the smooth channel. Under high Reynolds number conditions, the film cooling efficiency of the negative V-shaped ribs significantly increases, reaching 29-120%. The study demonstrates that rib shape and inlet Reynolds number have a signifi¬cant impact on the swirl intensity of the coolant in the film cooling holes, and fluid with a certain swirl intensity exhibits better film cooling efficiency.
KEYWORDS
PAPER SUBMITTED: 2024-01-19
PAPER REVISED: 2024-04-04
PAPER ACCEPTED: 2024-04-07
PUBLISHED ONLINE: 2024-06-22
DOI REFERENCE: https://doi.org/10.2298/TSCI240119135W
CITATION EXPORT: view in browser or download as text file
THERMAL SCIENCE YEAR 2024, VOLUME 28, ISSUE Issue 4, PAGES [3093 - 3106]
REFERENCES
  1. Zhu, R., et al., Combined-Hole Film Cooling Designs Based on the Construction of Antikidney Vortex Structure: A Review, Journal of Heat Transfer, 143 (2020), 3, pp. 030801-030813
  2. Perepezko, J. H., The Hotter the Engine, the Better, Science, 326 (2009), 5956, pp. 1068-1069
  3. Nourin, F. N., Amano, R. S., Review of Gas Turbine Internal Cooling Improvement Technology, Journal of Energy Resources Technology, 143 (2020), 8, 080801
  4. Jiang, G., et al., Flow and Heat Transfer Characteristics of Mist/Steam Two-Phase Flow in the U-Shaped Cooling Passage with 60 Deg. Ribs, International Communications in Heat and Mass Transfer, 105 (2019), June, pp. 73-83
  5. Zhang, J. C. H. M, High Performance Heat Transfer Ducts with Parallel Broken and V-Shaped Broken Ribs, International Journal of Heat and Mass Transfer, 105 (1992), 2, pp. 513-523
  6. Wang, L., Sunden, B.. An Experimental Investigation of Heat Transfer and Fluid-Flow in a Rectangular Duct with Broken V-Shapers Ribs, Experimental Heat Transfer, 17 (2004), 4, pp. 243-259
  7. Sriharsha, V., et al., Influence of Rib Height on the Local Heat Transfer Distribution and Pressure Drop in a Square Channel with 90° Continuous and 60° V-Broken Ribs, Applied Thermal Engineering, 29 (2009), 11-12, pp. 2444-2459
  8. Saumweber, C., et al., Effects of Entrance Crossflow Directions to Film Cooling Holes, Annals of the New York Academy of Sciences, 934 (2006), May, pp. 401-408
  9. Sakai, E., Takahashi, T., Experimental and Numerical Study on Effects of Turbulence Promoters on Flat Plate Film Cooling, ASME, Proceedings, Turbo Expo: Turbine Technical Conf. and Exposition, Vancouver, Canada, 2011
  10. Agata, Y., et al., Effects of Turbulence Promoters of Gas Turbine Blades on Film Cooling Performance, Journal of Thermal Science and Technology, 7 (2012), 4, pp. 603-618
  11. Wilfert, G., Wolff, S., Influence of Internal Flow on Film Cooling Effectiveness, Journal of Turbomachinery, 122 (2000), 2, pp. 327-333
  12. Zhang, H., et al., A Simplified Approach to Design Transverse Ribs Which Array Alternately in Rectangular Channel, Proceedings, ASME Turbo Expo: Power for Land, Sea, and Air, Glasgow, UK, 2010
  13. Li, C., et al., Effect of Coolant Crossflow on Film Cooling Effectiveness of Diffusion Slot Hole with and Without Ribs, Journal of Turbomachinery, 144 (2022), 9, 091005
  14. Xie, G., et al., Film Cooling Performance and Flow Characteristics of Internal Cooling Channels with Continuous/Truncated Ribs, International Journal of Heat and Mass Transfer, 105 (2017), Feb., pp. 67-75
  15. Sakai, E., et al., Experimental Study on Effects of Internal Ribs and Rear Bumps on Film Cooling Effectiveness, Journal of Turbomachinery, 135 (2013), 3, 031025
  16. Luo, J., et al., Numerical Investigation of Film Cooling Performance with Different Internal Flow Structures, Proceedings, ASME Turbo Expo 2014: Turbine Technical Conference and Exposition, Dusseldorf, Germany, 2014
  17. Liu, C. L., et al., Investigation on the Effects of Rib Orientation Angle on the Film Cooling with Ribbed Cross-Flow Coolant Channel, International Journal of Heat and Mass Transfer, 115 (2017), Part B, pp, 379-394
  18. Klavetter, S. R., et al., The Effect of Rib Turbulators on Film Cooling Effectiveness of Round Compound Angle Holes Fed by an Internal Cross-Flow, Journal of Turbomachinery, 138 (2016), 12, 121006
  19. Dančova, P., et al., Polyhedral Meshing in Numerical Analysis of Conjugate Heat Transfer, EPJ Web of Conferences, 180 (2018), 02096
  20. Jianxia, L., Research of External Film Cooling Performance of Turbine Blade with Different Internal Cooling Structures, Ph. D. thesis, Northwestern Polytechnical University, Xi'an, China, 2015

© 2024 Society of Thermal Engineers of Serbia. Published by the Vinča Institute of Nuclear Sciences, National Institute of the Republic of Serbia, Belgrade, Serbia. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution-NonCommercial-NoDerivs 4.0 International licence