Effect of blade tip structure on tip flow characteristics in turbine rotor
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摘要:
采用商业CFD软件Ansys CFX对3种叶尖结构模型进行数值仿真，选择
k-ω SST（shear stress transport）湍流模型对不同结构、吹风比、叶尖间隙条件下模型进行计算。结果表明：叶尖间隙直接影响进入叶尖凹槽区域的泄漏流流量。叶尖间隙变小，泄漏流受到的流动阻力增大，泄漏流流量相应下降；冷气吹风比增大后，冷气直接冲击机匣内壁面，在冲击点周围形成回流，冷气在叶尖区域凹槽涡的诱导下形成回流涡；构型3结构的凹槽中部隔板能够对进入凹槽的泄漏流产生阻挡作用，提高叶尖区域吸力面冷却效果。但隔板使得泄漏流在其左右两侧形成强度不同的凹槽涡和角涡，提高了热应力梯度。通过熵增分析，叶尖间隙对叶尖区域主流泄漏损失起决定性作用，叶尖间隙减小能够明显降低叶片尾缘区域损失。Abstract:Numerical simulations of three blade tip configurations were conducted using the commercial CFD software Ansys CFX. The
k-ω SST (shear stress transport) turbulence model was applied to compute the models under varying tip structures, blowing ratios, and blade tips. The findings demonstrated a direct correlation between the blade tip and the leakage flow entering the recessed area of the blade tip. Smaller blade tip gaps led to heightened flow resistance for the leakage flow, resulting in a corresponding reduction in leakage flow volume. When the cooling air blowing ratio increased, the cooling air directly impacted the interior casing wall, creating a backflow pattern around the point of impact. This backflow vortex was induced by the vortices within the crevice of the blade tip. In the case of configuration 3, the mid-section partition served as an obstruction to the entering leakage flow, thereby augmenting the cooling efficiency on the suction side of the blade tip. However, the partition also triggered the development of uneven crevice vortices and corner vortices on its opposing sides, leading to an elevation in thermal stress gradient. Entropy increment analysis underscored the pivotal role of the blade tip gap in determining the primary leakage loss in the blade tip region. Decreasing the blade tip gap markedly reduced losses in the blade trailing edge region.-
Key words:
- turbine blade /
- tip structure /
- flow characteristics /
- leakage flow /
- vortex structures
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图 7 3种构型不同叶尖间隙的叶尖区域流场（M=1.4）
Figure 7. Flow field in the blade tip for three configurations with different blade tip clearances （M=1.4）
图 8 不同叶尖间隙下叶片尾缘区熵增对比
Figure 8. Comparison of entropy increase in the trailing edge region for different blade tip clearances
图 9 不同构型尾缘区域熵增对比
Figure 9. Comparison of entropy increase in the trailing edge region for different configurations
图 12 构型2叶尖区域流场（C=0.6%h）
Figure 12. Flow field in the blade tip for configuration 2 （C=0.6%h）
图 13 构型2叶尖区域流场（C=1.2%h）
Figure 13. Flow field in the blade tip for configuration 2 （C=1.2%h）
图 14 构型2叶尖区域流场（C=1.8%h）
Figure 14. Flow field in the blade tip for configuration 2 （C=1.8%h）
图 16 采用Q准则识别的高雷诺数时构型2涡结构
Figure 16. Configuration 2 vortex structure identified using the Q criterion at high Reynolds number
表 1 叶栅通道参数表
Table 1. Blade cascade parameter table
参数 数值 叶片高度h/mm 51.1 弦长D/mm 43.8 栅距W/mm 36.2 叶尖间隙C/mm 0.315，0.63，0.945 进口构造角α/（°） 55 出口构造角β/（°） 19.7 
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[1] BOOTH T C,DODGE P R,HEPWORTH H K. Rotor-tip leakage: Part Ⅰ basic methodology[J]. Journal of Engineering for Power,1982,104(1): 154-161. doi: 10.1115/1.3227244 [2] AZAD G S,HAN J C,TENG Shuye,et al. Heat transfer and pressure distributions on a gas turbine blade tip[J]. Journal of Turbomachinery,2000,122(4): 717-724. doi: 10.1115/1.1308567 [3] ACHARYA S,YANG Huitao,PRAKASH C,et al. Numerical study of flow and heat transfer on a blade tip with different leakage reduction strategies[R]. ASME Paper GT2003-38617,2003. [4] CAMCI C,DEY D,KAVURMACIOGLU L. Aerodynamics of tip leakage flows near partial squealer rims in an axial flow turbine stage[J]. Journal of Turbomachinery,2005,127(1): 14-24. doi: 10.1115/1.1791279 [5] AMERI A A,STEINTHORSSON E,RIGBY D L. Effect of squealer tip on rotor heat transfer and efficiency[J]. Journal of Turbomachinery,1998,120(4): 753-759. doi: 10.1115/1.2841786 [6] KWAK J S,AHN J,HAN J C,et al. Heat transfer coefficients on the squealer tip and near-tip regions of a gas turbine blade with single or double squealer[J]. Journal of Turbomachinery,2003,125(4): 778-787. doi: 10.1115/1.1626684 [7] NASIR H,EKKAD S V,KONTROVITZ D M,et al. Effect of tip gap and squealer geometry on detailed heat transfer measurements over a high pressure turbine rotor blade tip[J]. Journal of Turbomachinery,2004,126(2): 221-228. doi: 10.1115/1.1731416 [8] PRAKASH C,LEE C P,CHERRY D G,et al. Analysis of some improved blade tip concepts[J]. Journal of Turbomachinery,2006,128(4): 639-642. doi: 10.1115/1.2220050 [9] 杨佃亮,丰镇平. 凹槽对动叶顶部流动和换热的影响[J]. 工程热物理学报,2007,28(6): 936-938. YANG Dianliang,FENG Zhenping. Study on tip leakage flow and heat transfer for a squealer tip blade[J]. Journal of Engineering Thermophysics,2007,28(6): 936-938. (in ChineseYANG Dianliang, FENG Zhenping. Study on tip leakage flow and heat transfer for a squealer tip blade[J]. Journal of Engineering Thermophysics, 2007, 28(6): 936-938. (in Chinese) [10] 杨佃亮,丰镇平. 叶顶凹槽对燃气透平动叶气动性能及叶顶传热的影响[J]. 西安交通大学学报,2008,42(7): 838-842. YANG Dianliang,FENG Zhenping. Effects of squealer tip on blade aerodynamic performance and tip heat transfer in gas turbine[J]. Journal of Xi’an Jiaotong University,2008,42(7): 838-842. (in ChineseYANG Dianliang, FENG Zhenping. Effects of squealer tip on blade aerodynamic performance and tip heat transfer in gas turbine[J]. Journal of Xi’an Jiaotong University, 2008, 42(7): 838-842. (in Chinese) [11] 杨佃亮,丰镇平. 叶顶形状对动叶顶部流动和传热的影响研究[J]. 西安交通大学学报,2008,42(5): 537-541. YANG Dianliang,FENG Zhenping. Effect of squealer geometry arrangements on tip leakage flow and heat transfer for turbine blade[J]. Journal of Xi’an Jiaotong University,2008,42(5): 537-541. (in ChineseYANG Dianliang, FENG Zhenping. Effect of squealer geometry arrangements on tip leakage flow and heat transfer for turbine blade[J]. Journal of Xi’an Jiaotong University, 2008, 42(5): 537-541. (in Chinese) [12] 李伟,乔渭阳,许开富,等. 一种改进的轴流涡轮叶尖对泄漏流影响的数值研究[J]. 航空学报,2008,29(5): 1125-1132. LI Wei,QIAO Weiyang,XU Kaifu,et al. Numerical study of influence on tip leakage flow in axial turbine with an improved tip[J]. Acta Aeronautica et Astronautica Sinica,2008,29(5): 1125-1132. (in ChineseLI Wei, QIAO Weiyang, XU Kaifu, et al. Numerical study of influence on tip leakage flow in axial turbine with an improved tip[J]. Acta Aeronautica et Astronautica Sinica, 2008, 29(5): 1125-1132. (in Chinese) [13] 包幼林,曾飞,甘明瑜,等. 凹槽叶顶构型对涡轮转子尖区漩涡演化的影响[J]. 推进技术,2022,43(4): 210575. BAO Youlin,ZENG Fei,GAN Mingyu,et al. Effects of squealer tip configuration on vortex evolution in tip region of turbine rotor[J]. Journal of Propulsion Technology,2022,43(4): 210575. (in ChineseBAO Youlin, ZENG Fei, GAN Mingyu, et al. Effects of squealer tip configuration on vortex evolution in tip region of turbine rotor[J]. Journal of Propulsion Technology, 2022, 43(4): 210575. (in Chinese) [14] 许承天,白波,李志刚,等. 涡轮动叶倾斜肩壁凹槽状叶顶气动性能研究[J]. 西安交通大学学报,2023,57(5): 46-57. XU Chengtian,BAI Bo,LI Zhigang,et al. Research on aerodynamic performance of gas turbine blade squealer tip with inclined rim[J]. Journal of Xi’an Jiaotong University,2023,57(5): 46-57. (in ChineseXU Chengtian, BAI Bo, LI Zhigang, et al. Research on aerodynamic performance of gas turbine blade squealer tip with inclined rim[J]. Journal of Xi’an Jiaotong University, 2023, 57(5): 46-57. (in Chinese) [15] 李伟,乔渭阳,许开富,等. 涡轮叶尖间隙泄漏流动主动控制数值模拟[J]. 航空动力学报,2008,23(7): 1260-1265. LI Wei,QIAO Weiyang,XU Kaifu,et al. Numerical simulation of active control on tip leakage flow in axial turbine[J]. Journal of Aerospace Power,2008,23(7): 1260-1265. (in ChineseLI Wei, QIAO Weiyang, XU Kaifu, et al. Numerical simulation of active control on tip leakage flow in axial turbine[J]. Journal of Aerospace Power, 2008, 23(7): 1260-1265. (in Chinese) [16] 轩笠铭,邹正平. 叶尖喷气对涡轮叶尖泄漏流动的影响研究[R]. 南京: 第五届空天动力联合会议,2020. XUAN Liming,ZOU Zhengping. Study on the effect of blade top jet on leakage flow of turbine tip[R]. Nanjing: The 5th Joint Conference on Aerospace Power,2020. (in ChineseXUAN Liming, ZOU Zhengping. Study on the effect of blade top jet on leakage flow of turbine tip[R]. Nanjing: The 5th Joint Conference on Aerospace Power, 2020. (in Chinese) [17] 于金杏,叶明亮,何坤,等. 压力侧冷却流对凹槽叶顶气膜冷却与传热性能的影响[J]. 西安交通大学学报,2022,56(3): 160-172. YU Jinxing,YE Mingliang,HE Kun,et al. Effect of pressure-side cooling flow on film cooling and heat transfer performance at squealer tip[J]. Journal of Xi’an Jiaotong University,2022,56(3): 160-172. (in ChineseYU Jinxing, YE Mingliang, HE Kun, et al. Effect of pressure-side cooling flow on film cooling and heat transfer performance at squealer tip[J]. Journal of Xi’an Jiaotong University, 2022, 56(3): 160-172. (in Chinese) [18] GAO Zhihong,NARZARY D,MHETRAS S,et al. Effect of inlet flow angle on gas turbine blade tip film cooling[J]. Journal of Turbomachinery,2009,131(3): 031005. [19] AHN J,MHETRAS S,HAN J C. Film-cooling effectiveness on a gas turbine blade tip using pressure-sensitive paint[J]. Journal of Heat Transfer,2005,127(5): 521-530. doi: 10.1115/1.1909208 [20] MHETRAS S,YANG Huitao,GAO Zhihong,et al. Film-cooling effectiveness on squealer cavity and rim walls of gas-turbine blade tip[J]. Journal of Propulsion and Power,2006,22(4): 898-899. doi: 10.2514/1.19201 [21] 于志强. 透平动叶气膜冷却的实验与数值研究[D]. 北京: 中国科学院大学,2020. YU Zhiqiang. Experimental and numerical investigation of turbine blade film cooling performance[D]. Beijing: University of Chinese Academy of Sciences,2020. (in ChineseYU Zhiqiang. Experimental and numerical investigation of turbine blade film cooling performance[D]. Beijing: University of Chinese Academy of Sciences, 2020. (in Chinese) [22] KE Zhaoqing,WANG Jianhua. Numerical investigations of pulsed film cooling on an entire turbine vane[J]. Applied Thermal Engineering,2015,87: 117-126. doi: 10.1016/j.applthermaleng.2015.05.022 [23] KAYS W,CRAWFORD M,WEIGAND B. Convective heat and mass transfer[M]. New York: McGraw Hill. 2005. [24] JONES T V. Theory for the use of foreign gas in simulating film cooling[J]. International Journal of Heat and Fluid Flow,1999,20(3): 349-354. doi: 10.1016/S0142-727X(99)00017-X [25] 林聚强. 涡轮叶片叶顶气膜冷却特性研究 [D]. 北京: 北京航空航天大学,2023. LIN Juqiang. Study of film cooling characteristics on turbine blade tip[D]. Beijing: Beihang University,2023. (in ChineseLIN Juqiang. Study of film cooling characteristics on turbine blade tip[D]. Beijing: Beihang University, 2023. (in Chinese) [26] 李会. 透平叶片顶部流动传热机理及冷却布局优化 [D]. 北京: 清华大学,2022. LI Hui. Aerothermal mechanism of blade tip leakage flow and cooling layout optimization design in gas turbines[D]. Beijing: Tsinghua University,2022. (in ChineseLI Hui. Aerothermal mechanism of blade tip leakage flow and cooling layout optimization design in gas turbines[D]. Beijing: Tsinghua University, 2022. (in Chinese) -
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