Numerical simulation of effects of contoured slot seal configuration on turbine performance
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摘要: 利用数值模拟的方法研究了波浪形非均匀间隙封严结构和均匀轴向间隙封严结构下轮缘封严气流对涡轮性能的影响.研究表明:燃气入侵与出流结构受到静盘、动盘及主流切向速度的影响,以低于动盘转速同向旋转,并改变了转子的进气条件,增强了压力面马蹄涡强度,因此对转子出口流场造成很大影响.封严气流与上游导叶尾迹的相互作用引起转子通道内熵增,造成涡轮效率的下降.与均匀轴向间隙封严结构相比,波浪形非均匀间隙封严结构使大的入侵与出流结构破碎为小的结构,对涡轮性能的负面影响减小,涡轮效率提高了0.9%.结果证明了波浪形非均匀间隙封严结构在具有较好的封严效果的同时提高了涡轮性能.Abstract: Effects of rim seal flow through uniform slot seal and contoured slot seal configurations on the turbine performance were investigated numerically. The results show that the gas ingress and egress structures are affected by stator disc, rotor disc and the tangential velocity in mainstream, and the rotating speed is less than that of rotor disc with the same direction. As a result, the flow patterns of rotor are changed, which strengthened the pressure side horseshoe vortex, thereby resulting in large changes of flow field of rotor exit. The interaction of seal flow and upstream vane weak induces the entropy rise in the rotor passages, leading to decrease of the turbine efficiency. Compared with uniform slot seal configuration, the contoured slot seal configuration collapses the big ingress and egress structures into smaller ones, and then has less negative effects on the turbine performance. The turbine efficiency is improved by 0.9%. The results prove that the contoured slot seal configuration has better turbine performance as well as better seal effectiveness.
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Key words:
- seal flow /
- mainstream flow /
- unsteady /
- turbine /
- rim
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[1] Cherry D, Wadia A, Beacock R, et al.Analytical investigation of a low pressure turbine with and without flow-path endwall gaps, seals and clearance features[R].ASME Paper GT2005-68492, 2005. [2] McLean C, Camci C, Glezer B.Mainstream aerodynamic effects due to wheelspace coolant injection in a high-pressure turbine stage:Part Ⅰ aerodynamic measurements in the stationary frame[J].Journal of Turbomachinery, 2001, 123(4):687-696. [3] McLean C, Camci C, Glezer B.Mainstream aerodynamic effects due to wheelspace coolant injection in a high-pressure turbine stage:Part Ⅱ aerodynamic measurements in the rotational frame[J].Journal of Turbomachinery, 2001, 123(4):697-703. [4] Hunter S, Manwaring S.Endwall cavity flow effects on gaspath aerodynamics in an axial flow turbine:Part Ⅰ experimental and numerical investigation[R].ASME Paper GT2000-651, 2000. [5] Ong J H P, Miller R J, Uchida S.The effect of coolant injection on the endwall flow of a high pressure turbine[R].ASME Paper GT2006-91060, 2006. [6] Erickson R D, Simon T W, Zhang L, et al.Experimental investigation of disc cavity leakage flow and hub endwall contouring in a linear rotor cascade[R].ASME Paper GT2011-46700, 2011. [7] Schuler P, Kurz W, Dullenkopf K, et al.The influence of different rim seal geometries on hot-gas ingestion and to-tal pressure loss in a low-pressure turbine[R].ASME Paper GT2010-22205, 2010. [8] Schuler P, Dullenkopf K, Bauer H J.Investigation of the influence of different rim seal geometries in a low pressure turbine[R].ASME Paper GT2011-45682, 2011. [9] Jenny P, Abhari R S, Rose M G, et al.Unsteady rotor hub passage vortex behavior in the presence of purge flow in an axial low pressure turbine[R].ASME Paper GT2012-69256, 2012. [10] Popovi Dc' I, Hodson H P.The effects of a parametric variation of the rim seal geometry on the interaction between hub leakage and mainstream flows in hp turbines[R].ASME Paper GT2012-68025, 2012. [11] Popovi Dc' I, Hodson H P.Improving turbine stage efficiency and sealing effectiveness through modifications of the rim seal geometry[R].ASME Paper GT2012-68026, 2012. [12] Knost D G, Thole K A, Duggleby A.Evaluating a three-dimensional slot design for the combustor-turbine interface[R].ASME Paper GT2009-60168, 2009. [13] Michael W, Axel D, Peter A G.Reducing the demand of coolant at the sidewall of a high pressure turbine cascade by means of slot width modulation[R].ASME Paper GT2012-68325, 2012. [14] 周杨, 牛为民, 邹正平, 等.轮毂封严气体对高压涡轮二次流动的影响[J].推进技术, 2006, 27(6):515-520. ZHOU Yang, NIU Weimin, ZOU Zhengping, et al.Effects of coolant injection from rim seals on secondary flow in a high-pressure turbine[J].Journal of Propulsion Technology, 2006, 27(6):515-520.(in Chinese) [15] ZHANG Jinghui, MA Hongwei.Numerical investigation of improving turbine sealing effectiveness through slot width modification of the rim seal[R].ASME Paper GT2013-95570, 2013. [16] Bohn D E, Decker A, Ma H, et al.Influence of sealing air mass flow on the velocity distribution in and inside the rim seal of the upstream cavity of a 1.5-stage turbine[R].ASME Paper GT2003-38459, 2003. [17] Bohn D E, Decker A, Ohlendorf N, et al.Influence of an axial and radial rim seal geometry on hot gas ingestion into the upstream cavity of a 1.5-stage tur-bine[R].ASME Paper GT2006-90453, 2006. [18] Sharma O P, Butler T L.Predictions of endwall losses and secondary flows in axial flow turbine cascades[J].Journal of Turbomachinery, 1987, 109(2):229-236. [19] Ralf J, Thomas Z, Klas L, et al.Numerical simulation of the unsteady flow field in an axial gas turbine rim seal configuration[R].ASME Paper GT2004-53829, 2004.
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