International Journal of Energy and Power Engineering

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The Design of Curved Endwall with Leading-edge Deformation

Received: 22 December 2019    Accepted: 30 December 2019    Published: 27 January 2020
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Abstract

The inlet boundary layer separates in front of the leading edge of the blade on the endwall and forms the pressure side leg of horseshoe vortex and the suction side one. The pressure side leg of the horseshoe vortex immediately moves toward to the suction side and form a stronger vortex, ”passage vortex”, in the cascade. These vortices mentioned above are called secondary flows which will result in an increase of secondary flow losses and a reduction of stage efficiency. In this paper, the flow characteristics are analyzed in the leading edge region and inside the cascade based on the numerical simulation results of the Langston cascade. A new type endwall design method, curved endwall structure combined with the deformation in the leading edge region, is established and optimized. It can be observed that the new structure can efficiently reduce the strength of the horseshoe vortex and suppress the generation of the leading edge separation line and saddle point. The uses of the new structure also decrease the pressure gradient between the pressure side and the suction side in the streamline direction, which suppresses the deviation of the pressure side horseshoe vortex from the pressure side of the endwall to the suction side and delays the formation position of the passage vortex. The rate of increase in the total pressure loss coefficient along the mainstream direction also decreases 25.34% in the exit of the cascade.

DOI 10.11648/j.ijepe.20200901.11
Published in International Journal of Energy and Power Engineering (Volume 9, Issue 1, January 2020)
Page(s) 1-10
Creative Commons

This is an Open Access article, distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution and reproduction in any medium or format, provided the original work is properly cited.

Copyright

Copyright © The Author(s), 2024. Published by Science Publishing Group

Keywords

NURBS, Secondary Flow, Leading-edge Position, Curved Endwall

References
[1] SHARMA O P, BUTLER T L. Predictions of Endwall Losses and Secondary Flows in Axial Flow Turbine Cascades [J]. Journal of Turbomachinery, 1986, 109 (2): 229.
[2] LANGSTON L S. Crossflows in a Turbine Cascade Passage [J]. Journal of Engineering for Gas Turbines & Power, 1980, 102 (4): 866.
[3] GOLDSTEIN R J, SPORES R A. Turbulent Transport on the Endwall in the Region Between Adjacent Turbine Blades [J]. Journal of Heat Transfer, 1988, 110 (4a): 862.
[4] WANG H P, OLSON S J, GOLDSTEIN R J, et al. Flow Visualization in a Linear Turbine Cascade of High Performance Turbine Blades [J]. Journal of Turbomachinery, 1995, 119 (1): 1-8.
[5] DENTON J D, DENTON J D. Loss Mechanisms in Turbomachines [J]. Journal of Turbomachinery, 1993, 115: 4 (4): V002T14A1.
[6] ZESS G A, THOLE K A, ZESS G A. Computational Design and Experimental Evaluation of Using a Leading Edge Fillet on a Gas Turbine Vane [J]. Journal of Turbomachinery, 2002, 124 (2): 167-75.
[7] SAUER H, MÜLLER R, VOGELER K. Reduction of Secondary Flow Losses in Turbine Cascades by Leading Edge Modifications at the Endwall [J]. Journal of Turbomachinery, 2001, 123 (2): 207-13.
[8] SHIH T I P, LIN Y L. Controlling Secondary-Flow Structure by Leading-Edge Airfoil Fillet and Inlet Swirl to Reduce Aerodynamic Loss and Surface Heat Transfer [J]. Journal of Turbomachinery, 2003, 125 (1): 48-56.
[9] WEI Z J, QIAO W Y, LIU J, et al. Reduction of endwall secondary flow losses with leading-edge fillet in a highly loaded low-pressure turbine [J]. Proceedings of the Institution of Mechanical Engineers Part A Journal of Power & Energy, 2016, 230 (2).
[10] SANGSTON K, LITTLE J, LYALL M E, et al. End Wall Loss Reduction of High Lift Low Pressure Turbine Airfoils Using Profile Contouring—Part II: Validation; proceedings of the ASME Turbo Expo 2013: Turbine Technical Conference and Exposition, F, 2014 [C].
[11] LYALL M E, KING P I, CLARK J P, et al. Endwall Loss Reduction of High Lift Low Pressure Turbine Airfoils Using Profile Contouring: Part I — Airfoil Design; proceedings of the ASME Turbo Expo 2013: Turbine Technical Conference and Exposition, F, 2014 [C].
[12] ATKINS, M. J. Endwall profiling in axial flow turbines [J]. Gastroenterology, 1984, 15 (5): 490-4.
[13] VARPE M K, PRADEEP A M. Benefits of Nonaxisymmetric Endwall Contouring in a Compressor Cascade With a Tip Clearance [J]. Journal of Fluids Engineering, 2015, 137 (5):
[14] SAHA A K, ACHARYA S. Computations of Turbulent Flow and Heat Transfer Through a Three-Dimensional Nonaxisymmetric Blade Passage [J]. Journal of Turbomachinery, 2008, 130 (3): 538-44.
[15] TAREMI F, SJOLANDER S A, PRAISNER T J. Application of Endwall Contouring to Transonic Turbine Cascades: Experimental Measurements at Design Conditions; proceedings of the ASME 2011 Turbo Expo: Turbine Technical Conference and Exposition, F, 2011 [C].
[16] ROSE M G. Non-Axisymmetric Endwall Profiling in the HP NGV’s of an Axial Flow Gas Turbine; proceedings of the ASME 1994 International Gas Turbine and Aeroengine Congress and Exposition, F, 1994 [C].
[17] ZIMMERMANN T W, CURKOVIC O, WIRSUM M, et al. COMPARISON OF 2D AND 3D TURBINE AIRFOILS IN COMBINATION WITH NONAXISYMMETRIC ENDWALL CONTOURING [J]. Journal of Turbomachinery, 2016, 139 (6).
[18] BERGH J, SNEDDEN G, MEYER C. Optimization of Non-Axisymmetric End Wall Contours for the Rotor of a Low Speed, 1 1/2 Stage Research Turbine With Unshrouded Blades; proceedings of the ASME Turbo Expo 2012: Turbine Technical Conference and Exposition, F, 2012 [C].
[19] LYNCH S P, SUNDARAM N, THOLE K A, et al. Heat Transfer for a Turbine Blade With Non-Axisymmetric Endwall Contouring; proceedings of the ASME Turbo Expo 2009: Power for Land, Sea, and Air, F, 2011 [C].
[20] MENSCH A E, THOLE K A. Effects of non-axisymmetric endwall contouring and film cooling on the passage flowfield in a linear turbine cascade [J]. Experiments in Fluids, 2016, 57 (1): 1.
[21] REUTTER O, HEMMERT-POTTMANN S, HERGT A, et al. Endwall Contouring and Fillet Design for Reducing Losses and Homogenizing the Outflow of a Compressor Cascade [J]. 2014, V02AT37A007-V02AT37A.
[22] TURGUT Ö H, CAMCı C. A Nonaxisymmetric Endwall Design Methodology for Turbine Nozzle Guide Vanes and its Computational Fluid Dynamics Evaluation; proceedings of the ASME 2011 International Mechanical Engineering Congress and Exposition, F, 2011 [C].
[23] TURGUT Ö H, CAMCı C. Experimental Investigation and Computational Evaluation of Contoured Endwall and Leading Edge Fillet Configurations in a Turbine NGV; proceedings of the ASME Turbo Expo 2012: Turbine Technical Conference and Exposition, F, 2012 [C].
[24] GRAZIANI R A, BLAIR M F, TAYLOR R J, et al. An Experimental Study of Endwall and Airfoil Surface Heat Transfer in a Large Scale Turbine Blade Ca [J]. Journal of Engineering for Gas Turbines & Power, 1980, 102 (2): 602.
[25] SIEVERDING C H. Recent Progress in the Understanding of Basic Aspects of Secondary Flows in Turbine Blade Passages [J]. Journal of Engineering for Gas Turbines & Power, 1984, 107 (2): 248-57.
[26] HOLLEY B M. Surface measurements of flow in a plane turbine cascade [J]. Dissertations & Theses - Gradworks, 2008.
[27] SCHOBEIRI M T, LU K. Endwall Contouring Using Continuous Diffusion: A New Method and its Application to a Three-Stage High Pressure Turbine [J]. Journal of Turbomachinery, 2014, 136 (1): 787-97.
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    Zhang Xuyang. (2020). The Design of Curved Endwall with Leading-edge Deformation. International Journal of Energy and Power Engineering, 9(1), 1-10. https://doi.org/10.11648/j.ijepe.20200901.11

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    ACS Style

    Zhang Xuyang. The Design of Curved Endwall with Leading-edge Deformation. Int. J. Energy Power Eng. 2020, 9(1), 1-10. doi: 10.11648/j.ijepe.20200901.11

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    AMA Style

    Zhang Xuyang. The Design of Curved Endwall with Leading-edge Deformation. Int J Energy Power Eng. 2020;9(1):1-10. doi: 10.11648/j.ijepe.20200901.11

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  • @article{10.11648/j.ijepe.20200901.11,
      author = {Zhang Xuyang},
      title = {The Design of Curved Endwall with Leading-edge Deformation},
      journal = {International Journal of Energy and Power Engineering},
      volume = {9},
      number = {1},
      pages = {1-10},
      doi = {10.11648/j.ijepe.20200901.11},
      url = {https://doi.org/10.11648/j.ijepe.20200901.11},
      eprint = {https://article.sciencepublishinggroup.com/pdf/10.11648.j.ijepe.20200901.11},
      abstract = {The inlet boundary layer separates in front of the leading edge of the blade on the endwall and forms the pressure side leg of horseshoe vortex and the suction side one. The pressure side leg of the horseshoe vortex immediately moves toward to the suction side and form a stronger vortex, ”passage vortex”, in the cascade. These vortices mentioned above are called secondary flows which will result in an increase of secondary flow losses and a reduction of stage efficiency. In this paper, the flow characteristics are analyzed in the leading edge region and inside the cascade based on the numerical simulation results of the Langston cascade. A new type endwall design method, curved endwall structure combined with the deformation in the leading edge region, is established and optimized. It can be observed that the new structure can efficiently reduce the strength of the horseshoe vortex and suppress the generation of the leading edge separation line and saddle point. The uses of the new structure also decrease the pressure gradient between the pressure side and the suction side in the streamline direction, which suppresses the deviation of the pressure side horseshoe vortex from the pressure side of the endwall to the suction side and delays the formation position of the passage vortex. The rate of increase in the total pressure loss coefficient along the mainstream direction also decreases 25.34% in the exit of the cascade.},
     year = {2020}
    }
    

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  • TY  - JOUR
    T1  - The Design of Curved Endwall with Leading-edge Deformation
    AU  - Zhang Xuyang
    Y1  - 2020/01/27
    PY  - 2020
    N1  - https://doi.org/10.11648/j.ijepe.20200901.11
    DO  - 10.11648/j.ijepe.20200901.11
    T2  - International Journal of Energy and Power Engineering
    JF  - International Journal of Energy and Power Engineering
    JO  - International Journal of Energy and Power Engineering
    SP  - 1
    EP  - 10
    PB  - Science Publishing Group
    SN  - 2326-960X
    UR  - https://doi.org/10.11648/j.ijepe.20200901.11
    AB  - The inlet boundary layer separates in front of the leading edge of the blade on the endwall and forms the pressure side leg of horseshoe vortex and the suction side one. The pressure side leg of the horseshoe vortex immediately moves toward to the suction side and form a stronger vortex, ”passage vortex”, in the cascade. These vortices mentioned above are called secondary flows which will result in an increase of secondary flow losses and a reduction of stage efficiency. In this paper, the flow characteristics are analyzed in the leading edge region and inside the cascade based on the numerical simulation results of the Langston cascade. A new type endwall design method, curved endwall structure combined with the deformation in the leading edge region, is established and optimized. It can be observed that the new structure can efficiently reduce the strength of the horseshoe vortex and suppress the generation of the leading edge separation line and saddle point. The uses of the new structure also decrease the pressure gradient between the pressure side and the suction side in the streamline direction, which suppresses the deviation of the pressure side horseshoe vortex from the pressure side of the endwall to the suction side and delays the formation position of the passage vortex. The rate of increase in the total pressure loss coefficient along the mainstream direction also decreases 25.34% in the exit of the cascade.
    VL  - 9
    IS  - 1
    ER  - 

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Author Information
  • CSIC 704 Research Institute, Shanghai, China

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