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
THERMAL SCIENCE YEAR
2024, VOLUME
28, ISSUE
Issue 4, PAGES [3093 - 3106]
- 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
- Perepezko, J. H., The Hotter the Engine, the Better, Science, 326 (2009), 5956, pp. 1068-1069
- Nourin, F. N., Amano, R. S., Review of Gas Turbine Internal Cooling Improvement Technology, Journal of Energy Resources Technology, 143 (2020), 8, 080801
- 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
- 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
- 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
- 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
- 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
- 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
- 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
- Wilfert, G., Wolff, S., Influence of Internal Flow on Film Cooling Effectiveness, Journal of Turbomachinery, 122 (2000), 2, pp. 327-333
- 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
- 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
- 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
- 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
- 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
- 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
- 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
- Dančova, P., et al., Polyhedral Meshing in Numerical Analysis of Conjugate Heat Transfer, EPJ Web of Conferences, 180 (2018), 02096
- 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