Hostname: page-component-cd9895bd7-q99xh Total loading time: 0 Render date: 2024-12-25T19:42:50.227Z Has data issue: false hasContentIssue false
  • English
  • Français

Numerical investigations on the effect of blade tip winglet on leakage flow loss reduction for a zero inlet swirl turbine rotor

Published online by Cambridge University Press:  11 February 2022

Qinghui Zhou Open the ORCID record for Qinghui Zhou [Opens in a new window] ,
Wei Zhao Open the ORCID record for Wei Zhao [Opens in a new window] ,
Qingjun Zhao ,
Xiuming Sui  and
Jianzhong Xu
Qinghui Zhou
Affiliation:
Institute of Engineering Thermophysics, Chinese Academy of Sciences, Beijing, China School of Aeronautics and Astronautics, University of Chinese Academy of Sciences, Beijing, China
Wei Zhao*
Affiliation:
Institute of Engineering Thermophysics, Chinese Academy of Sciences, Beijing, China Innovation Academy for Light-duty Gas Turbine, Chinese Academy of Sciences, Beijing, China School of Aeronautics and Astronautics, University of Chinese Academy of Sciences, Beijing, China
Qingjun Zhao
Affiliation:
Institute of Engineering Thermophysics, Chinese Academy of Sciences, Beijing, China Innovation Academy for Light-duty Gas Turbine, Chinese Academy of Sciences, Beijing, China School of Aeronautics and Astronautics, University of Chinese Academy of Sciences, Beijing, China
Xiuming Sui
Affiliation:
Institute of Engineering Thermophysics, Chinese Academy of Sciences, Beijing, China Innovation Academy for Light-duty Gas Turbine, Chinese Academy of Sciences, Beijing, China
Jianzhong Xu
Affiliation:
Institute of Engineering Thermophysics, Chinese Academy of Sciences, Beijing, China Innovation Academy for Light-duty Gas Turbine, Chinese Academy of Sciences, Beijing, China School of Aeronautics and Astronautics, University of Chinese Academy of Sciences, Beijing, China
*
E-mail: [email protected]
Get access Rights & Permissions [Opens in a new window]

Abstract

The tip leakage flow generates a large amount of aerodynamic losses in a zero inlet swirl turbine rotor (ZISTR), which directly uses the axial exit flow downstream of a combustion chamber without any nozzles. To reduce the tip leakage flow loss and improve the efficiency for the ZISTR, a front suction side winglet is employed on the blade tip, and the effect of winglet width is numerically investigated to explore its design space. It is found that, a suction side leading edge horseshoe vortex (SHV) on the blade tip plays a crucial role in mitigating the tip leakage flow loss. This SHV rotates in the reverse direction to the leakage vortex, so it tends to break the formation of the leakage vortex near the front part of suction side. With a larger winglet width, the SHV stays longer time on the blade tip and leaves it at a further downstream location. This increases the time and the contact area of the interaction between the SHV and the leakage vortex, so the leakage vortex is further weakened. Thus, the tip leakage flow loss is reduced, and the efficiency is improved. However, a larger winglet width also increases the heat load of the blade due to a larger blade surface area. The ZISTR designed with the winglet width equal to 2.1% blade pitch achieves a great trade-off between efficiency and heat load that the efficiency is improved by 0.85% at an expense of 1.2% increment of the heat load. Besides, for the blade using this winglet, the mechanical stress due to the centrifugal, aerodynamic and thermal load is acceptable for the engine application. This investigation indicates a great potential in the improvement of efficiency for the ZISTR using a blade tip winglet designed on the front suction side.

Keywords

Zero inlet swirl turbine rotorLeakage flow lossBlade tip winglet
Type
Research Article
Information
The Aeronautical Journal , Volume 126 , Issue 1302: The 25th ISABE Conference Special Issue – Part II , August 2022 , pp. 1370 - 1393
Check for updates
Copyright
© The Author(s), 2022. Published by Cambridge University Press on behalf of Royal Aeronautical Society

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Zhao, W., Wu, B. and Xu, J. Aerodynamic Design and Analysis of a Multistage Vaneless Counter-Rotating Turbine, ASME J. Turbomach., 2015, 137, pp 061008-1-12.CrossRefGoogle Scholar
Zhao, W., Zhao, Q. and Sui, X. Numerical Investigation on Loss Mechanism and Performance Improvement for a Zero Inlet Swirl Turbine Rotor, ASME Turbo Expo: Turbomachinery Technical Conference & Exposition, GT2017-63220, 2017.CrossRefGoogle Scholar
Booth, T.C., Dodge, P.R. and Hepworth, H.K. Rotor-Tip Leakage Part I—Basic Methodology, ASME Paper No. 81-GT-71, 1981.Google Scholar
Ameri, A.A., Steinthorsson, E. and Rigby, D.L. Effect of Squealer Tip on Rotor Heat Transfer and Efficiency, ASME J. Turbomach., 1998, 120, pp 753–759.CrossRefGoogle Scholar
Camci, C., Dey, D. and Kavurmacioglu, L. Aerodynamics of Tip Leakage Flow Near Partial Squealer Rims in an Axial Flow Turbine Stage, ASME J. Turbomach., 2005, 127, pp 14–24.CrossRefGoogle Scholar
Key, N. and Arts, T. Comparison of turbine tip leakage flow for flat tip and squealer tip geometries at high speed conditions, ASME J. Turbomach., 2006, 128, pp 213–220.CrossRefGoogle Scholar
Mischo, B., Behr, T. and Abhari, R.S. Flow physics and profiling of recessed blade tips: impact on performance and heat load, ASME J. Turbomach., 2008, 130, 021008.CrossRefGoogle Scholar
Lee, S.W. and Chae, B.J. Effects of squealer rim height on aerodynamic losses downstream of a high-turning turbine rotor blade, Exp. Therm. Fluid Sci., 2008, 32, (2008), pp 1440–1447.CrossRefGoogle Scholar
Wheeler, A.P.S., Korakianitis, T. and Banneheke, S. Tip leakage losses in subsonic and transonic blade rows, ASME J. Turbomach., 2013, 135, 011019.CrossRefGoogle Scholar
Li, W., Jiang, H., Zhang, Q. and Lee, S.W. Squealer tip leakage flow characteristics in transonic condition, ASME J. Eng. Gas Turbines Power, 2014, 136, 042601.CrossRefGoogle Scholar
Zou, Z., Shao, F. and Li, Y. Dominant flow structure in the squealer tip gap and its impact on turbine aerodynamic performance, Energy, 2017, 138, (nov.1), pp 167–184.CrossRefGoogle Scholar
Yaras, M.I. and Sjolander, S. Measurements of the Effects of Winglets on Tip-Leakage Losses in a Linear Turbine Cascade, Paper No. ISABE 91-7011, pp. 127–135.Google Scholar
Harvey, N.W. and Ramsden, K. A computational study of a novel turbine rotor partial shroud, ASME J. Turbomach., 2001, 123, pp 534–543.CrossRefGoogle Scholar
Dey, D. and Camci, C. Aerodynamic tip desensitization of an axial turbine rotor using tip platform extensions, ASME Paper 2001-GT-0484 (2001).CrossRefGoogle Scholar
Kang, D.B. and Lee, S.W. Heat/mass transfer over the plane tip equipped with a full coverage winglet in a turbine cascade: part 1 – winglet bottom surface data, Int. J. Heat Mass Transf., 2015, 88, 965–973.CrossRefGoogle Scholar
Lee, S.W., Kim, S.U. and Kim, K.H. Aerodynamic performance of winglets covering the tip gap inlet in a turbine cascade, Int. J. Heat Fluid Flow, 2012, 34, pp 36–46.CrossRefGoogle Scholar
Seo, Y.C. and Lee, S.W. Tip gap flow and aerodynamic loss generation in a turbine cascade equipped with suction-side winglets, J. Mech. Sci. Technol., 2013, 27, (3), pp 703–712.CrossRefGoogle Scholar
Zhou, C., Hodson, H., Tibbott, I., et al. Effects of Winglet Geometry on the Aerodynamic Performance of Tip Leakage Flow in a Turbine Cascade, ASME J. Turbomach., 2013, 135, (5), pp 051009.1–051009.10.Google Scholar
Coull, J.D., Atkins, N.R. and Hodson, H.P. Winglets for Improved Aerothermal Performance of High Pressure Turbines, ASME J. Turbomach., 2014, 136, (9), pp. 091007.1–091007.11.CrossRefGoogle Scholar
Lee, S.W., Cheon, J.H. and Zhang, Q. The effect of full coverage winglets on tip leakage aerodynamics over the plane tip in a turbine cascade, Int. J. Heat Fluid Flow, 2014, 45, pp 23–32.CrossRefGoogle Scholar
Cheon, J.H. and Lee, S.W. Winglet geometry effects on tip leakage loss over the plane tip in a turbine cascade, J. Mech. Sci. Technol., 2018, 32,pp 1633–1642.CrossRefGoogle Scholar
Seo, Y.C. and Lee, S.W. Aerodynamic losses for squealer tip with different winglets, J. Mech. Sci. Technol., 2019, 33, (2), pp 639–647.CrossRefGoogle Scholar
Zhou, C. and Zhong, F. A Novel Suction Side Winglet Design Method for High Pressure Turbine Rotor Tips, ASME J. Turbomach., 2017, 139, (11), pp 111002.1–111002.11.CrossRefGoogle Scholar
Saha, A.K., Acharya, S., Bunker, R.S. and Prakash, C. Blade tip leakage flow and heat transfer with pressure-side winglet, Int. J. Rotating Mach., 2006, pp 1–15.CrossRefGoogle Scholar
Schabowski, Z. and Hodson, H. The reduction of over tip leakage loss in unshrouded axial turbines using winglets and squealers, ASME J. Turbomach., 2014, 136, 041001.CrossRefGoogle Scholar
Schabowski, Z., Hodson, H., Giacche, D., Power, B. and Stokes, M.R. Aeromechanical optimization of a winglet-squealer tip for an axial turbine, ASME J. Turbomach., 2014, 136, 071004.CrossRefGoogle Scholar
Tallman, J.A. A Computation Study of Tip Desensitization in Axial Flow Turbines, The Pennsylvania State University, 2002, Pennsylvania.Google Scholar
Greizer, E.M., Tan, C.S. and Graf, M.B. Internal flow: concepts and applications, Cambridge University Press, 2004,New York.CrossRefGoogle Scholar
Zlatinov, M.B., Tan, C.S., Montgomery, M., Islam, T. and Harris, M. Turbine hub and shroud sealing flow loss mechanisms. ASME J. Turbomach., 2012; 134, (6), 061027.CrossRefGoogle Scholar
Denton, J.D. The 1993 IGTI Scholar Lecture: Loss Mechanisms in Turbomachines, ASME J. Turbomach., 1993, 115, (4), 621.CrossRefGoogle Scholar
Krishnababu, S.K., Newton, P.J., Dawes, W.N. et al. Aerothermal Investigations of Tip Leakage Flow in Axial Flow Turbines—Part I: Effect of Tip Geometry and Tip Clearance Gap, ASME J. Turbomach., 2009, 131, (1), 011006.CrossRefGoogle Scholar
El-Ghandour, M., Mori, K. and Nakamura, Y. Desensitization of Tip Clearance Effects in Axial Flow Turbines, J. Fluid Sci. Technol., 2010, 5, (2), pp 317–330.CrossRefGoogle Scholar