Effects of tip clearance height on flow and heat transfer characteristics in a transonic turbine rotor
-
摘要:
以经典跨声速涡轮叶片为研究对象，采用数值模拟方法研究了5种叶尖间隙高度（0.23、0.46、0.69、0.92 mm和1.38 mm）对涡轮动叶叶尖及附近区域流动换热特性及气动性能的影响规律。研究结果表明：随着叶尖间隙增大，叶尖超声速区域范围向前缘扩展，流动分离点后移，激波与膨胀波干涉效应增强，流场复杂性加剧。1.38 mm间隙高度下面平均努塞尔数（
Nu ）较0.23 mm间隙增大了9.9%。叶尖泄漏涡和马蹄涡的强度与尺度均随间隙增大而增强，相互作用加剧；然而，面平均总压损失系数随间隙增大呈下降趋势，1.38 mm间隙下的损失较0.23 mm间隙降低了1.993%，表明小间隙下泄漏流的强约束与掺混集中是导致较高气动损失的主要原因。此外，绝对泄漏量随间隙增大显著增加，但单位间隙高度下的泄漏率随之减小。Abstract:Taking a classic transonic turbine blade as the research object, this study adopts numerical simulation methods to investigate the influence laws of five tip clearance heights (0.23, 0.46, 0.69, 0.92 mm, and 1.38 mm) on the flow and heat transfer characteristics as well as aerodynamic performance of the turbine rotor tip and its adjacent regions. The results show that with the increase in tip clearance, the scope of the supersonic region on the blade tip expands toward the leading edge, the flow separation point shifts rearward, the interference effect between shock waves and expansion waves is enhanced, and the complexity of the flow field is aggravated. The area-averaged Nusselt Number (
Nu ) at a clearance height of 1.38 mm is increased by 9.9% compared with that at a clearance height of 0.23 mm. Both the strength and scale of the tip leakage vortex and the horseshoe vortex are enhanced with the increase in clearance, and their interaction is intensified. However, the area-averaged total pressure loss coefficient shows a decreasing trend with the increase in clearance, and the loss at a clearance height of 1.38 mm is reduced by 1.993% compared with that at a clearance height of 0.23 mm, which indicates that the strong confinement and concentrated mixing of the leakage flow in small clearances are the main causes of higher aerodynamic losses. In addition, the absolute leakage mass flow increases significantly with the increase in clearance, while the leakage rate per unit clearance height decreases accordingly.-
Key words:
- transonic turbine /
- tip clearance /
- shockwave structure /
- Nusselt number (Nu) /
- tip leakage /
- total pressure loss
-
图 3 数值模拟计算网格示意
Figure 3. Schematic diagram of the computational grid for numerical simulation
图 5 不同叶尖间隙下中截面马赫数分布
Figure 5. Distribution of Mach number at mid-section under different tip clearances
图 6 不同叶尖间隙下叶尖表面极限流线分布
Figure 6. Distribution of limiting streamlines on the blade tip surface at different tip clearance
图 7 基于Q准则下的不同叶尖间隙叶尖区域涡量分布
Figure 7. Vortex distribution on the blade tip region with different tip clearances based on the Q-criterion
图 8 不同叶尖间隙下M1截面密度梯度分布
a 膨胀波1；b 入射激波；c 诱导激波；d 膨胀波2；e 再附着激波；f 反射激波；g 吸力面角激波；h 膨胀波3。
Figure 8. Density gradient distribution at the M1 section with different tip clearances
图 9 不同叶尖间隙下M1截面中线压力分布
Figure 9. Pressure distribution along the midline of the M1 section with different tip clearances
图 10 不同叶尖间隙下叶尖表面Nu数云图
Figure 10. Contours of heat transfer coefficient on the blade tip surface under different tip clearances
图 11 不同叶尖间隙下叶尖表面努塞尔数展向平均分布
Figure 11. Spanwise-averaged distribution of heat transfer coefficient on the blade tip surface under different tip clearances
图 12 不同叶尖间隙下面平均努塞尔数
Figure 12. Area-averaged heat transfer coefficient values under different tip clearances
图 13 基于Q准则下的不同间隙叶尖附近区域涡核区域
Figure 13. Vortex core regions near the blade tip region with different tip clearances based on the Q-criterion
图 14 不同叶尖间隙下叶尖附近沿流向截面总压损失分布
Figure 14. Total pressure loss distribution in streamwise sections near the blade tip under different tip clearances
图 15 不同叶尖间隙下叶尖区域总压损失
Figure 15. Total pressure loss on the blade tip region under different tip clearances
图 16 不同叶尖间隙下叶尖区域泄漏量
Figure 16. Leakage flow on the blade tip region under different tip clearances
图 17 不同叶尖间隙下叶尖附近两侧的压力差
Figure 17. Pressure difference across the two sides near the blade tip under different tip clearances
表 1 数值模拟计算条件
Table 1. Numerical simulation calculation conditions
计算条件 数值 主流进口总温/K 1633 主流进口总压/MPa 1.324 出口背压/MPa 0.2795 转速/（r/min） 13232 壁面温度/K 绝热/ 1020 进口湍流度/% 5 
下载: 导出CSV
表 2 网格无关性验证
Table 2. Grid independence verification
网格编号 网格数目/104 面平均努塞尔数$ \overline{\overline{Nu}} $ 1 200 519.4 2 400 586.0 3 600 636.0 4 800 636.2
下载: 导出CSV
-
[1] DENTON J D. Loss mechanisms in turbomachines[J]. Journal of Turbomachinery, 1993, 115(4): 621-656. [2] KEY N L, ARTS T. Comparison of turbine tip leakage flow for flat tip and squealer tip geometries at high-speed conditions[J]. Journal of Turbomachinery, 2006, 128(2): 213-220. doi: 10.1115/1.2162183 [3] YANG Huitao, CHEN H C, HAN J C. Film-cooling prediction on turbine blade tip with various film hole configurations[J]. Journal of Thermophysics and Heat Transfer, 2006, 20(3): 558-568. doi: 10.2514/1.18422 [4] DU Kun, WANG Xubo, HUANG Xiaoyang, et al. Turbine blade tip aerothermal characteristics considering the influences of cavity tip shaping[J]. International Journal of Thermal Sciences, 2024, 204: 109234. doi: 10.1016/j.ijthermalsci.2024.109234 [5] DU Kun, LI Huarong, SUNDEN B, et al. Effects of ribbed-cavity tip on the blade tip aerothermal performance in a high pressure turbine stage[J]. Journal of Thermal Science, 2023, 32(2): 800-811. doi: 10.1007/s11630-023-1771-5 [6] 杜昆, 王旭博, 惠娜, 等. 涡轮凹槽叶尖气膜孔形对叶尖冷却特性影响的数值研究[J]. 航空动力学报, 2025, 40(4): 91-100. DU Kun, WANG Xubo, HUI Na, et al. Numerical study on influences of hole shapes on turbine cavity tip film cooling characteristics[J]. Journal of Aerospace Power, 2025, 40(4): 91-100. (in Chinese doi: 10.13224/j.cnki.jasp.20240510DU Kun, WANG Xubo, HUI Na, et al. Numerical study on influences of hole shapes on turbine cavity tip film cooling characteristics[J]. Journal of Aerospace Power, 2025, 40(4): 91-100. (in Chinese) doi: 10.13224/j.cnki.jasp.20240510 [7] KIM J H, LEE S Y, CHUNG J T. Numerical analysis of the aerodynamic performance & heat transfer of a transonic turbine with a partial squealer tip[J]. Applied Thermal Engineering, 2019, 152: 878-889. doi: 10.1016/j.applthermaleng.2019.02.066 [8] 蒋红梅, 张子扬, 卢少鹏. 凹槽叶尖尾缘设计对高压涡轮气动性能的影响[J]. 航空动力学报, 2024, 39(6): 20230512. JIANG Hongmei, ZHANG Ziyang, LU Shaopeng. Influence of trailing edge designs of squealer tips on aerodynamic performance of high-pressure turbine[J]. Journal of Aerospace Power, 2024, 39(6): 20230512. (in Chinese doi: 10.13224/j.cnki.jasp.20230512JIANG Hongmei, ZHANG Ziyang, LU Shaopeng. Influence of trailing edge designs of squealer tips on aerodynamic performance of high-pressure turbine[J]. Journal of Aerospace Power, 2024, 39(6): 20230512. (in Chinese) doi: 10.13224/j.cnki.jasp.20230512 [9] 林聚强, 由儒全, 李海旺, 等. 叶尖结构对涡轮动叶端区流动特性影响[J]. 航空动力学报, 2025, 40(5): 20230556. LIN Juqiang, YOU Ruquan, LI Haiwang, et al. Effect of blade tip structure on tip flow characteristics in turbine rotor[J]. Journal of Aerospace Power, 2025, 40(5): 20230556. (in ChineseLIN Juqiang, YOU Ruquan, LI Haiwang, et al. Effect of blade tip structure on tip flow characteristics in turbine rotor[J]. Journal of Aerospace Power, 2025, 40(5): 20230556. (in Chinese) [10] GAO Jie, ZHENG Qun, NIU Xiying, et al. Aerothermal characteristics of a transonic tip flow in a turbine cascade with tip clearance variations[J]. Applied Thermal Engineering, 2016, 107: 271-283. doi: 10.1016/j.applthermaleng.2016.06.155 [11] CAO Zhiyuan, ZHANG Xiang, WANG Chuxuan, et al. A study on the flow physics of a supersonic partial admission impulse turbine for different tip clearances[J]. Aerospace Science and Technology, 2022, 123: 107469. doi: 10.1016/j.ast.2022.107469 [12] WEI Zuojun, REN Guangming, GAN Xiaohua, et al. Influence of shock wave on loss and breakdown of tip-leakage vortex in turbine rotor with varying backpressure[J]. Applied Sciences, 2021, 11(11): 4991. doi: 10.3390/app11114991 [13] XIA Kailong, CHEN Huayin, DENG Hefang, et al. Impact of non-axisymmetric tip clearance on the aerodynamic and aeroelastic stabilities of a transonic compressor[J]. Aerospace Science and Technology, 2024, 153: 109457. doi: 10.1016/j.ast.2024.109457 [14] QIN Taojie, TONG Zixiang, LI Dong, et al. Aerothermal performance of cavity tip with flow structure effects in a transonic high-pressure turbine blade[J]. Energy, 2024, 291: 130411. doi: 10.1016/j.energy.2024.130411 [15] YANG Yi, MA Hongwei, XIAO Anqi, et al. Shock wave structures and vortex unsteadiness in the tip region of a transonic turbine cascade under different conditions[J]. Physics of Fluids, 2024, 36(10): 106117. doi: 10.1063/5.0223927 [16] ANTO K, XUE S, NG W F, et al. Effects of tip clearance gap and exit Mach number on turbine blade tip and near-tip heat transfer[C]//Volume 3C: Heat Transfer. American Society of Mechanical Engineers, 2013: V03CT14A005. [17] 杜昆, 李军. 跨声速涡轮叶顶间隙流动传热特性的数值研究[J]. 西安交通大学学报, 2016, 50(4): 147-152. DU Kun, LI Jun. Numerical investigations on flow and heat transfer characteristics of transonic turbine blade tips[J]. Journal of Xi’an Jiaotong University, 2016, 50(4): 147-152. (in Chinese doi: 10.7652/xjtuxb201604022DU Kun, LI Jun. Numerical investigations on flow and heat transfer characteristics of transonic turbine blade tips[J]. Journal of Xi’an Jiaotong University, 2016, 50(4): 147-152. (in Chinese) doi: 10.7652/xjtuxb201604022 [18] 陈彦龙, 张超炜, 李广勇. 跨声速离心压气机激波与叶顶泄漏流相互作用数值研究[J/OL]. 航空动力学报, (2025-03-27)[2025-09-06]. https://doi.org/10.13224/j.cnki.jasp.20240788. CHEN Yanlong, ZHANG Chaowei, LI Guangyong. Numerical study on interaction between shock wave and tip leakage flow in transonic centrifugal compressor[J/OL]. Journal of Aerospace Power, (2025-03-27)[2025-09-06]. https://doi.org/10.13224/j.cnki.jasp.20240788. (in ChineseCHEN Yanlong, ZHANG Chaowei, LI Guangyong. Numerical study on interaction between shock wave and tip leakage flow in transonic centrifugal compressor[J/OL]. Journal of Aerospace Power, (2025-03-27)[2025-09-06]. https://doi.org/10.13224/j.cnki.jasp.20240788. (in Chinese) [19] COULL J D, ATKINS N R, HODSON H P. Winglets for improved aerothermal performance of high pressure turbines[J]. Journal of Turbomachinery, 2014, 136(9): 091007. doi: 10.1115/1.4026909 [20] 钟兢军, 赵傲, 胡义, 等. 叶尖小翼对跨声速压气机级稳定工作裕度的影响[J]. 航空动力学报, 2024, 39(1): 20220236. ZHONG Jingjun, ZHAO Ao, HU Yi, et al. Effect of tip winglets on stable operating margin of transonic compressor stage[J]. Journal of Aerospace Power, 2024, 39(1): 20220236. (in Chinese doi: 10.13224/j.cnki.jasp.20220236ZHONG Jingjun, ZHAO Ao, HU Yi, et al. Effect of tip winglets on stable operating margin of transonic compressor stage[J]. Journal of Aerospace Power, 2024, 39(1): 20220236. (in Chinese) doi: 10.13224/j.cnki.jasp.20220236 [21] 姜超, 王志宽, 乐贵高, 等. 周向非均匀叶尖间隙对某转子旋转不稳定现象影响的数值模拟[J]. 航空动力学报, 2024, 39(12): 20220973. JIANG Chao, WANG Zhikuan, LE Guigao, et al. Numerical simulation of effect of circumferential non-uniform tip clearance on rotating instability in a rotor[J]. Journal of Aerospace Power, 2024, 39(12): 20220973. (in ChineseJIANG Chao, WANG Zhikuan, LE Guigao, et al. Numerical simulation of effect of circumferential non-uniform tip clearance on rotating instability in a rotor[J]. Journal of Aerospace Power, 2024, 39(12): 20220973. (in Chinese) [22] ZHONG Fangpan, ZHOU Chao, MA H, et al. Heat transfer of winglet tips in a transonic turbine cascade[J]. Journal of Engineering for Gas Turbines and Power, 2017, 139: 012605. doi: 10.1115/1.4034208 [23] ZHONG Fangpan, ZHOU Chao. Tip gap size effects on thermal performance of cavity-winglet tips in transonic turbine cascade with endwall motion[J]. Journal of the Global Power and Propulsion Society, 2017, 1: CR5JBC. doi: 10.22261/CR5JBC [24] ZHOU Chao. Aerothermal performance of different tips in transonic turbine cascade with end-wall motion[J]. Journal of Propulsion and Power, 2014, 30(5): 1316-1327. doi: 10.2514/1.B34963 [25] MANSOURI Z. Aerodynamic and heat transfer performances of a highly loaded transonic turbine rotor with upstream generic rim seal cavity[J]. Propulsion and Power Research, 2021, 10(4): 317-331. doi: 10.1016/j.jppr.2021.11.003 [26] JACKSON A J, WHEELER A P S, AINSWORTH R W. An experimental and computational study of tip clearance effects on a transonic turbine stage[J]. International Journal of Heat and Fluid Flow, 2015, 56: 335-343. doi: 10.1016/j.ijheatfluidflow.2015.09.001 [27] WHEELER A P S, SANDBERG R D. Direct numerical simulations of a transonic tip flow with free-stream disturbances[C]//ASME 2013 Turbine Blade Tip Symposium. American Society of Mechanical Engineers, 2013: TBTS2013-2037, V001T01A002. -
点击查看大图
计量
- 文章访问数: 51
- HTML浏览量: 55
- PDF量: 6
- 被引次数: 0