Experimental research of the plate film cooling characteristics of backward-expanding shoulder arm hole
-
摘要: 提出一种新型气膜冷却孔型——渐扩后倾肩臂孔，运用压力敏感漆（PSP）实验技术，研究其与圆孔、肩臂孔的气膜冷却性能差异，并采用N2和CO2气体作为冷却气，对比分析了密度比1.0和1.5情况下吹风比（Br=0.5~2.0）对渐扩后倾肩臂孔平板气膜冷却性能的影响。结果表明：在相同密度比、吹风比条件下，渐扩后倾肩臂孔方案冷却效率优于圆孔和肩臂孔（肩臂孔略高于圆孔）。在密度比为1.0的情况下，当测量点离孔的距离与孔入口直径的比值x/D < 15时，渐扩后倾肩臂孔方案的展向平均气膜冷却效率随着吹风比的增大呈递减趋势；当x/D>15时，冷却效率在Br=1.0时最大。在密度比为1.5的情况下，渐扩后倾肩臂孔方案的展向平均气膜冷却效率随着吹风比的增大呈先增大后减小的趋势，在Br=1.0时冷却效率最大。分析认为：不同密度比情况下，吹风比对渐扩后倾肩臂孔冷却性能的影响差异，主要是由于密度比较小时，冷却气出口速度更大，使冷却气更易吹离冷却壁面。Abstract: A new turbine film-cooling hole shape that is named the backward-expanding shoulder arm hole is designed. By using N2 and CO2 gas as the cooling gas, the film cooling perfor-mance with different density ratios of the backward-expanding shoulder arm hole, the circular hole and the shoulder arm hole is studied in the paper. The results show that, under the same conditions the film cooling efficiency of the backward-expanding shoulder arm hole is better than that of the circular hole and the shoulder arm hole, and the film cooling efficiency of the shoulder arm hole is slightly higher than that of the circular hole. The average film cooling efficiency decreases with the increase of the blowing ratio in the place where x/D < 15, and the average film cooling efficiency at Br=1.0 reaches maximum in the place where x/D > 15 when the density ratio is 1.0. The average film cooling efficiency increases first and then decreases with the increase of the blowing ratio, and the average film cooling efficiency is highest at Br=1.0 is maximum. The analysis indicates that as the outlet velocity is higher when the density is lower under the same blowing ratio, so that the cooling gas is more easily blown away from the cooling wall, the blow-ing ratio has effects on the film cooling efficiency of the backward-expanding shoulder arm hole.
-
Key words:
- gas turbine /
- film cooling /
- backward-expanding shoulder arm hole /
- hole geometry /
- PSP
-
图 1 不同气膜孔通道结构几何示意图
Figure 1. Geometric sketch of the channel structure for different gas film holes
图 7 不同孔型的展向平均气膜冷却效率对比图
Figure 7. Comparison of spanwise average film cooling efficiency with different hole geometries
图 8 不同孔型的气膜冷却效率分布云图
Figure 8. Distribution of gas film cooling efficiency with different hole geometries
图 9 吹风比和密度比对展向平均气膜冷却效率的影响
Figure 9. Effect of blowing ratio and density ratio on spanwise average film cooling efficiency
-
[1] 朱延鑫, 谭晓茗, 郭文, 等.出流孔型对平板气膜冷却影响机理的研究[J].推进技术, 2013, 34(4):499-505. http://d.old.wanfangdata.com.cn/Periodical/tjjs201304011Zhu Y X, Tan X M, Guo W, et al. Numerical simulation on effects of different film cooling holes on plat[J]. Journal of Propulsion Technology, 2013, 34(4):499-505. http://d.old.wanfangdata.com.cn/Periodical/tjjs201304011 [2] 葛绍岩, 徐靖中.气膜冷却[M].北京:科学出版社, 1985.Ge S Y, Xu J Z. Film cooling[M]. Beijing:Science Press, 1985. [3] 李少华, 宋东辉, 刘建红, 等.不同孔型平板气膜冷却的数值模拟[J].中国电机工程学报, 2006, 26(17):112-116. doi: 10.3321/j.issn:0258-8013.2006.17.020Li S H, Song D H, Liu J H, et al. Numerical simulations of flat plate film cooling using respectively different shaped jet holes[J]. Proceedings of the CSEE, 2006, 26(17):112-116. doi: 10.3321/j.issn:0258-8013.2006.17.020 [4] Leylek J H, Zerkle R D. Discrete jet film-cooling:a comparison of computational results with experiments[J]. ASME Journal of Transaction, 1994, 116(3):358-368. [5] Goldstein R J, Eckert E R, Burggraf F. Effects of hole geometry and density on three-dimensional film cooling[J]. International Journal of Heat & Mass Transfer, 1974, 17(5):595-607. [6] Okita Y, Nishiura M. Film effectiveness performance of an arrow head-shaped film-cooling hole geometry[J]. Journal of Turbomachinery, 2007, 129(2):331-339. doi: 10.1115/1.2437781 [7] Kusterer K, Bohn D, Sugimoto T, et al. Double-jet ejection of cooling air for improved film cooling[J]. Journal of Turboma-chinery, 2007, 129(4); 809-815. doi: 10.1115/1.2720508 [8] Heidmann J D, Ekkad S. A novel antivortex turbine film-cooling hole concept[J]. Journal of Turbomachinery, 2008, 130(3):031020. doi: 10.1115/1.2777194 [9] Mhetras S, Yang H T, Gao Z H, et al. Film-cooling effectiveness on squealer rim walls and squealer cavity floor of a gas turbine blade tip using pressure sensitive paint[R]. GT2005-68387, 2005. [10] Suryanarayanan A, Mhetras S P, Schobeiri M T, et al. Film-cooling effectiveness on a rotating blade platform[J]. Journal of Turbomachinery, 2009, 131(1):011014. doi: 10.1115/1.2752184 [11] Gao Z H, Wright L M, Han J. Assessment of steady state PSP and transient ir measurement techniques for leading edge film cooling[C]//Proc of ASME 2005 International Mechanical Engineering Congress and Expositon. 2005. [12] Shadid J N, Eckert E R G. The mass transfer to heat transfer in fluids with temperature-dependent properties[J]. Journal of Turbomachinery, 1991, 113(1):27-33. doi: 10.1115/1.2927734 [13] Caciolli G, Facchini B, Picchi A, et al. Comparison between PSP and TLC steady state techniques for adiabatic effectiveness measurement on a multiperforated plate[J]. Experimental Thermal and Fluid Science, 2013, 48:122-133. doi: 10.1016/j.expthermflusci.2013.02.015 [14] Jones T V. Theory for the use of foreign gas in simulating film cooling[J]. International Journal of Heat & Fluid Flow, 1999, 20:349-354. http://www.wanfangdata.com.cn/details/detail.do?_type=perio&id=2bb9574e2809f39f5fb4ddd510c7ed46 [15] Yang Z F, Hu H. An experimental investigation on the trailing edge cooling of turbine blades by using PIV and PSP techniques[J]. Propulsion & Power Research, 2012, 1(1):36-47. http://www.wanfangdata.com.cn/details/detail.do?_type=perio&id=CC0212472186 [16] Ekkad S V, Zapata D, Han J C. Film Effectiveness over a flat surface with air and CO2 injection through compound angle holes using a transient liquid crystal image method[J]. Journal of Turbomachinery, 1997, 119(3):587-593. doi: 10.1115/1.2841162 [17] Saumweber C, Schulz A, Wittig S. Free-stream turbulence effects on film cooling with shaped holes[J]. Journal of Turbomachinery, 2003, 125(1):65-73. doi: 10.1115/1.1515336 [18] Gustafson R, Mahmood G I, Acharya S. Flowfield in a film-cooled three-dimensional endwall passage: aerodynamic mea-surements[C]. ASME Paper 2007, No. GT2007-28154. [19] Bunker R S. A review of shaped hole turbine film-cooling technology[J]. Journal of Heat Transfer Transactions of the ASME, 2005, 127(4):441-453. doi: 10.1115/1.1860562 [20] Ekkad S V, Ou S, Rivir R B. Effect of jet pulsation and duty cycle on film cooling from a single jet on a leading edge model[J]. Journal of Turbomachinery, 2006, 128(3):564-571. doi: 10.1115/1.2185122 [21] Bogard D G, Thole K A. Gas turbine film cooling[J]. Journal of Propulsion & Power, 2005, 22(2):249-270. http://d.old.wanfangdata.com.cn/Periodical/zgdjgcxb201129016 [22] Sinha A K, Bogard D, Crawford M E. Film-cooling effectiveness downstream of a single row of holes with variable density ratio[J]. Journal of Turbomachinery, 1991, 113(3):441-449. doi: 10.1115-1.2927894/ [23] 李佳, 韩昌, 任静, 等.基于压敏漆的带横槽气膜冷却实验与数值研究[J].工程热物理学报, 2010, 31(2):239-242. http://www.wanfangdata.com.cn/details/detail.do?_type=perio&id=QK201000068855Li J, Han C, Ren J, et al. Film cooling performance of the embedded holes in trenches with compound angles[J]. Journal of Engineering Thermophysics, 2010, 31(2):239-242. http://www.wanfangdata.com.cn/details/detail.do?_type=perio&id=QK201000068855 [24] Kapadia S, Roy S, Heidmann J. First hybrid turbulence modeling for turbine blade cooling[J]. Journal of Thermophysics & Heat Transfer, 2015, 18(1):154-156. http://www.wanfangdata.com.cn/details/detail.do?_type=perio&id=1223dac0471065d9431efadde430a255 [25] Bunker R S. Film cooling effectiveness due to discrete holes within a transverse surface slot[C]//Proc of ASME Turbo Expo 2002: Power for Land, Sea, and Air. 2002. -
下载:
点击查看大图
图(10)
计量
- 文章访问数: 99
- HTML全文浏览量: 64
- PDF下载量: 1
- 被引次数: 0
