ACTA AERONAUTICAET ASTRONAUTICA SINICA >
Aerodynamic performance of a variable geometry turbine cascade using a vane-end winglet
Received date: 2015-12-17
Revised date: 2016-04-29
Online published: 2016-05-04
Supported by
National Natural Science Foundation of China (51406039); Natural Science Foundation of Heilongjiang Province of China (QC2016059)
In a high endwall-angle variable-geometry turbine, the rotating shaft end can lead to a serious deterioration of endwall flow fields when the variable vane rotates. A winglet is proposed to be applied to the variable vane casing-end to overcome this problem and then reduce the vane-end leakage flow. Combined with the low-speed wind tunnel test, numerical investigation is performed by solving Reynolds-averaged Navier-Stokes equations in conjunction with a standard k-ω two-equation turbulence model. The endwall flow fields and loss distribution of the variable vane with winglets are analyzed. The effects of vane turning are discussed. The vane-end cavity-winglet structure is then proposed, and the aerodynamic performance and its sensitivity to vane-end clearance height are evaluated. The results show that the variable vane with winglets can not only avoid the deterioration of endwall flow fields caused by vane turning, but also reduce the vane-end clearance leakage driving force, thus leading to improved endwall flow performance of variable vanes at all turning angles. Besides, the variable vane with cavity-winglets can further reduce the leakage flow, and the total pressure loss coefficient is reduced overall by 8.9% as compared to the baseline.
Key words： variable geometry turbine; winglet tip; cavity tip; aerodynamic loss; cascade
GAO Jie , ZHENG Qun , LIU Pengfei , WEI Ming . Aerodynamic performance of a variable geometry turbine cascade using a vane-end winglet[J]. ACTA AERONAUTICAET ASTRONAUTICA SINICA, 2016 , 37(12) : 3615 -3624 . DOI: 10.7527/S1000-6893.2016.0139
[1] KARSTENSEN K W, WIGGINS J O. A variable-geometry power turbine for marine gas turbines[J]. Journal of Turbomachinery, 1990, 112(2):165-174.
[2] MOFFITT T P, WHITNEY W J, SCHUM H J. Performance of a single-stage turbine as affected by variable stator area:AIAA-1969-0525[R]. Reston:AIAA, 1969.
[3] 宋力强, 王永泓. 变几何燃气涡轮损失模型的分析[J]. 燃气轮机技术, 2004, 17(2):35-40. SONG L Q, WANG Y H. Analysis on the loss model of variable geometry turbines[J]. Gas Turbine Technology, 2004, 17(2):35-40(in Chinese).
[4] QIU C, SONG H F, WANG Y H, et al. Performance estimation of variable geometry turbines[J]. Proceedings of the Institution of Mechanical Engineers, Part A:Journal of Power and Energy, 2009, 223(4):441-449.
[5] RAZINSKY E H, KUZIAK W R. Aerothermodynamic performance of a variable nozzle power turbine stage for an automotive gas turbine[J]. Journal of Engineering for Gas Turbines and Power, 1977, 99(4):587-592.
[6] 刘顺隆, 冯永明, 刘敏, 等. 船用燃气轮机动力涡轮可调导叶级的流场结构[J]. 热能动力工程, 2005, 20(2):120-124. LIU S L, FENG Y M, LIU M, et al. The flow field structure of the power-turbine variable-area nozzle stage of a marine gas turbine[J]. Journal of Engineering for Thermal Energy and Power, 2005, 20(2):120-124(in Chinese).
[7] 冯永明, 刘顺隆, 刘敏, 等. 船用燃气轮机变几何动力涡轮大攻角流动特性的三维数值模拟[J]. 热能动力工程, 2005, 20(5):459-463. FENG Y M, LIU S L, LIU M, et al. Three-dimensional numerical simulation of the flow characteristics at a large incidence of the variable-geometry power turbine of a marine gas turbine[J]. Journal of Engineering for Thermal Energy and Power, 2005, 20(5):459-463(in Chinese).
[8] YUE G Q, YIN S Q, ZHENG Q. Numerical simulation of flow fields of variable geometry turbine with spherical endwalls or nonuniform clearance:GT2009-59737[R]. New York:ASME, 2009.
[9] 陈升, 邱超, 宋华芬. 涡轮平面叶栅变几何试验研究[J]. 热能动力工程, 2011, 26(1):7-12. CHEN S, QIU C, SONG H F. Variable geometry experimental study of a turbine plane cascade[J]. Journal of Engineering for Thermal Energy and Power, 2011, 26(1):7-12(in Chinese).
[10] 马超, 臧述升, 黄名海. 变几何涡轮动叶栅流场的PIV实验研究[J]. 动力工程学报, 2014, 34(6):458-462. MA C, ZANG S S, HUANG M H. PIV flow field measurement for rotor blade cascade of a variable geometry turbine[J]. Journal of Chinese Society of Power Engineering, 2014, 34(6):458-462(in Chinese).
[11] 潘波, 陶海亮, 赵洪雷, 等. 可调导叶端壁间隙泄漏损失控制方法研究[J]. 工程热物理学报, 2013, 34(4):618-623. PAN B, TAO H L, ZHAO H L, et al. Investigation on the control strategy of variable guide vane endwall gap leakage loss[J]. Journal of Engineering Thermophysics, 2013, 34(4):618-623(in Chinese).
[12] GAO J, ZHENG Q, YUE G Q, et al. Variable geometry design of a high endwall angle power turbine for marine gas turbines:GT2015-43173[R]. New York:ASME, 2015.
[13] MISCHO B, BURDET A, ABHARI, et al. Influence of stator-rotor interaction on the aerothermal performance of recess blade tips:GT2008-50496[R]. New York:ASME, 2008.
[14] EL-GHANDOUR M, MORI K, NAKAMURA Y. Desensitization of tip clearance effects in axial flow turbines[J]. Journal of Fluid Science and Technology, 2010, 5(2):317-330.
[15] 高杰, 郑群. 叶顶凹槽形态对动叶气动性能的影响[J]. 航空学报, 2013, 34(2):218-226. GAO J, ZHENG Q. Effect of squealer tip geometry on rotor blade aerodynamic performance[J]. Acta Aeronautica et Astronautica Sinica, 2013, 34(2):218-226(in Chinese).
[16] 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):091007-1-091007-11.
[17] LEE S W, KIM S U, KIM K H. Aerodynamic performance of winglets covering the tip gap inlet in a turbine cascade[J]. International Journal of Heat and Fluid Flow, 2012, 34:36-46.
[18] GAO J, ZHENG Q, ZHANG Z Y, et al. Aero-thermal performance improvements of unshrouded turbines through management of tip leakage and injection flows[J]. Energy, 2014, 69:648-660.
[19] NIU M S, ZANG S S. Experimental and numerical investigations of tip injection on tip clearance flow in an axial turbine cascade[J]. Experimental Thermal and Fluid Science, 2011, 35(6):1214-1222.
[20] 刘宇, 闫锦生, 卫嘉, 等. 燃气轮机动力涡轮可转导叶系统:ZL202348444U[P]. 2012-07-25. LIU Y, YAN J S, WEI J, et al. Variable-geometry vane system for gas turbine power turbines:China:ZL202348444U[P]. 2012-07-25(in Chinese).
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