SpringerLink
Log in

Effect of Squealer Tip with Deep Scale Depth on the Aero-thermodynamic Characteristics of Tip Leakage Flow

  • Published:
Journal of Thermal Science Aims and scope Submit manuscript

Abstract

In this paper, the aero-thermal performance of squealer tips with deep-scale depth is numerically investigated in an axial flow turbine, which is compared with the squealer tip with traditional cavity depth. Numerical methods were validated with experimental data. The effect of cavity depth and tip clearance was considered. The numerical results show that for the squealer tip with conventional cavity depth, the size of the reflux vortex enlarges as the cavity depth increases. The velocity and uniformity of high entropy production rate (EPR) inside the cavity reduce obviously with the cavity develo** into deep-scale. However, the increase of depth 10% of the blade span (H) leads to enlargement of cavity volume, which increases the total entropy production rate. And the overall dimensionless entropy production rate (DEPR) of gap and cavity obtains a maximum increase of 43.54% in contrast to the case with 1%H depth cavity. As a result, the relative leakage mass flow rate reduces by 20.6% as the cavity depth increases from 1% to 10%. Given the heat transfer, as the cavity significantly increases to 10%H, the enhanced cavity volume results in a more enormous cavity vortex with low velocity covering the floor, which weakens the convective heat transfer intensity and reduces the area of high heat transfer. The normalized average heat transfer coefficient at the cavity bottom reduces by 40.26% compared to the cavity depth of 1%H. In addition, the deep-scale cavity is more effective in inhibiting leakage flow at smaller tip clearance. The reduction amplitude of normalized average heat transfer coefficient at the squealer floor decreases as tip clearance increases, which reduces at most by about 72.6% for the tip clearance of 1%H.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Log in via an institution

Subscribe and save

Springer+ Basic
EUR 32.99 /Month
  • Get 10 units per month
  • Download Article/Chapter or Ebook
  • 1 Unit = 1 Article or 1 Chapter
  • Cancel anytime
Subscribe now

Buy Now

Price includes VAT (Brazil)

Instant access to the full article PDF.

Institutional subscriptions

Similar content being viewed by others

Abbreviations

C ax :

axial chord of the blade

C p :

static pressure loss coefficient

d i :

depth of the squealer

H :

span of the blade

h :

heat transfer coefficient

h ave :

area-averaged heat transfer coefficient

Nu :

Nusslet number

Q :

Heat flux

s̄ ij :

strain rate tensor

W :

width of squealer

ε :

relative leakage mass flow rate

λ T :

turbulent heat transfer coefficient

μ T :

turbulent viscosity coefficient

τ :

tip clearance height

DEPR:

dimensionless entropy production rate

EPR:

entropy production rate

HPT:

high-pressure turbine

LE:

leading-edge of blade

PS:

pressure side of blade

SS:

suction side of blade

TE:

trailing edge of blade

TKE:

turbulent kinetic energy

TLF:

tip leakage flow

TLV:

tip leakage vortex

TPV:

tip passage vortex

in/out:

inlet/outlet of the computational domain

t:

total

References

  1. Bunker R.S., Axial turbine blade tips: function, design, and durability. Journal of Propulsion and Power, 2006, 22(2): 271–285.

    Article  Google Scholar 

  2. Bunker R.S., A review of turbine blade tip heat transfer. Annals of the New York Academy of Science, 2001, 934(1): 64–79.

    Article  ADS  Google Scholar 

  3. Sun Q., Ji D., Guo H., Research on gas turbine blade material and Fatigue Creep. Turbine Technology, 2017, 59(2): 81–83.

    Google Scholar 

  4. Booth T.C., Dodge P.R., Hepworth H.K., Rotor-tip leakage Part I: basic methodology. ASME, 1981, Paper 81-GT-71.

    Google Scholar 

  5. Yamamoto A., Interaction mechanisms between tip leakage flow and the passage vortex in a linear turbine rotor cascade. Journal of Turbomachinery, 1988, 110(3): 329–338.

    Article  Google Scholar 

  6. Denton J.D., Loss mechanisms in turbomachines. Journal of Turbomachinery, 1993, 115(4): 621–656.

    Article  Google Scholar 

  7. Azad G.S., Han J.C., Teng S., et al., Heat transfer and pressure distributions on a gas turbine blade Tip. Journal of Turbomachinery, 2000, 122(4): 717–724.

    Article  Google Scholar 

  8. Kwak J.S., Han J.C., Heat transfer coefficients of a turbine blade-tip and near-tip regions. Journal of Thermophysics & Heat Transfer, 2003, 17(3): 297–303.

    Article  Google Scholar 

  9. Azad GM.S., Han J.C., Bunker R.S., Lee C.P., Effect of squealer geometry arrangement on a gas turbine blade tip heat transfer. Journal of Heat Transfer, 2002, 124: 452–459.

    Article  Google Scholar 

  10. Zeng F., Du J., Huang L., et al., An experimental method for squealer tip flow field considering relative casing motion. Chinese Journal of Aeronautics, 2020, 33(7): 1942–1952.

    Article  Google Scholar 

  11. Zeng F., Zhang W., Wang Y., et al., Effects of squealer geometry of turbine blade tip on the tip-leakage flow and loss. Journal of Thermal Science, 2021, 30(4): 1376–1387.

    Article  ADS  Google Scholar 

  12. Zhou C., Hodson H., Numerical investigation of thermal performance of unshrouded HP turbine blade tips. International Journal of Turbo & Jet Engines, 2009, 26(4): 277–284.

    Article  ADS  Google Scholar 

  13. Kavurmacioglu L., Maral H., Senel C.B., et al., Performance of partial and cavity type squealer tip of a HP turbine blade in a linear cascade. International Journal of Aerospace Engineering, 2018, Article: 3262164.

    Google Scholar 

  14. Yang H., Ching H., et al., Turbine rotor with various tip configurations flow and heat transfer prediction. Journal of Thermophysics & Heat Transfer, 2006, 20(1): 80–91.

    Article  Google Scholar 

  15. Liu J.J., Li P., Zhang C., et al., Flow field and heat transfer past an unshrouded gas turbine blade tip with different shapes. Journal of Thermal Science, 2013, 22(2): 128–134.

    Article  ADS  Google Scholar 

  16. Zhong J., Wu W., Han S., Research progress of tip winglet technology in compressor. Journal of Thermal Science, 2021, 30(1): 18–31.

    Article  ADS  Google Scholar 

  17. Cui W., Wang X., Yao F., Zhao Q., Liu Y., Liu L., Wang C., Yang L., Effects of width variation of pressure-side winglet on tip flow structure in a transonic rotor. Journal of Thermal Science, 2022, 31(1): 141–150.

    Article  ADS  Google Scholar 

  18. Zou Z., Shao F., Li Y., et al., Dominant flow structure in the squealer tip gap and its impact on turbine aerodynamic performance. Energy, 2017, 138: 167–184.

    Article  Google Scholar 

  19. Zou Z., Xuan L., Chen Y., et al., Effects of flow structure on heat transfer of squealer tip in a turbine rotor blade. International Communications in Heat and Mass Transfer, 2020, 114: 104588.

    Article  Google Scholar 

  20. Kim J., Seo W., Chung H., et al., Effect of shelf squealer tip configuration on aerothermal performance of gas turbine blade. International Journal of Thermal Sciences, 2021, 168: 107056.

    Article  Google Scholar 

  21. Yan X., Huang Y., He K., et al., Numerical investigations into the effect of squealer-winglet blade tip modifications on aerodynamic and heat transfer performance. International Journal of Heat & Mass Transfer, 2016, 103: 242–253.

    Article  Google Scholar 

  22. Choi S.M., Bang M., Moon H., et al., Wake effects on heat transfer from a turbine blade tip with different configurations and its corresponding shroud. International Communications in Heat and Mass Transfer, 2021, 126: 105333.

    Article  Google Scholar 

  23. Du K., Li Z., Li J., et al., Influences of a multi-cavity tip on the blade tip and the over tip casing aerothermal performance in a high-pressure turbine cascade. Applied Thermal Engineering, 2019, 147: 347–360.

    Article  Google Scholar 

  24. Jiang S., Li Z., Li J., et al., Effects of the novel rib layouts on the tip leakage flow pattern and heat transfer performance of turbine blade. Proceedings of the Institution of Mechanical Engineers Part G: Journal of Aerospace Engineering, 2020, 234(8): 1446–1459.

    Article  Google Scholar 

  25. Lee S.W., Chae B.J., Effects of squealer rim height on aerodynamic losses downstream of a high-turning turbine rotor blade. Experimental Thermal & Fluid Science, 2008, 32(8): 1440–1447.

    Article  Google Scholar 

  26. Zhou C., Effects of endwall motion on thermal performance of cavity tips with different squealer width and height. International Journal of Heat and Mass Transfer, 2015, 91: 1248–1258.

    Article  Google Scholar 

  27. Shi W., Chen P., Li X., et al., Uncertainty quantification of the effects of squealer tip geometry deviation on aerothermal performance. Proceedings of the Institution of Mechanical Engineers Part A Journal of Power and Energy, 2020, 234(7): 1026–1038.

    Article  Google Scholar 

  28. Kwak J., Ahn J., Han J., Effects of rim location, rim height, and tip clearance on the tip and near tip region heat transfer of a gas turbine blade. International Journal of Heat and Mass Transfer, 2004, 47(26): 5651–5663.

    Article  Google Scholar 

  29. Zhou C., Hodson H., Squealer geometry effects on aerothermal performance of tip-leakage flow of cavity tips. Journal of Propulsion and Power, 2012, 28(3): 556–567.

    Article  Google Scholar 

  30. Park J., Lee D., Rhee D., et al., Heat transfer and film cooling effectiveness on the squealer tip of a turbine blade. Energy, 2014, 72: 331–343.

    Article  Google Scholar 

  31. Sakaoglu S., Kahveci H.S., Effect of cavity depth on thermal performance of a cooled blade tip under rotation. International Journal of Heat and Mass Transfer, 2019, 143: 118561.

    Article  Google Scholar 

  32. Bang M., Choi S., Sohn H., et al., Effects of unsteady wakes on heat transfer of blade tip and shroud. International Communications in Heat and Mass Transfer, 2018, 97: 125–135.

    Article  Google Scholar 

  33. Senel C.B., Maral H., Kavurmacioglu L.A., et al., An aerothermal study of the influence of squealer width and height near a HP turbine blade. International Journal of Heat & Mass Transfer, 2018, 120: 18–32.

    Article  Google Scholar 

  34. Kwak, J.S., and Han, J.C., Heat transfer coefficient on a gas turbine blade tip and near tip regions. AIAA-2002-3012, 2002. DOI: https://doi.org/10.2514/6.2002-3012.

    Book  Google Scholar 

  35. Timko L.P., Energy efficient engine high pressure turbine component test performance report, 1984.

    Google Scholar 

  36. Moore J., Moore J.G., Entropy production rates from viscous flow calculations: Part I A turbulent boundary layer flow. Proc. ASME 1983 International Gas Turbine Conference and Exhibit, 1983, V001T001A032. DOI: https://doi.org/10.1115/83-gt-70.

    Google Scholar 

  37. Kwak J., Han J., Heat transfer coefficient on the squealer tip and near squealer tip regions of a gas turbine blade. Journal of Heat Transfer, 2003, 125(4): 669–677.

    Article  Google Scholar 

  38. Ye M., He K., Yan X., Influence of wear damages on aerodynamic and heat transfer performance in squealer tip gap. Applied Thermal Engineering, 2019, 159: 1–19.

    Article  Google Scholar 

  39. Ameri A.A., Steinthorsson E., Rigby D.L., Effect of squealer tip on rotor heat transfer and efficiency. Journal of Turbomachinery, 1998, 120(4): 753–759.

    Article  Google Scholar 

  40. Yang D.L., Feng Z.P., Tip leakage flow and heat transfer predictions for turbine blades. Proceedings of ASME Turbo Expo, 2007, ASME, Paper GT2007-27728.

    Google Scholar 

  41. He K., Investigation of film cooling and heat transfer on a turbine blade squealer tip. Applied Thermal Engineering, 2017, 110: 630–647.

    Article  Google Scholar 

  42. Li F., Wang H., Liu Z., et al., Comparisons of blade tip phantom cooling effectiveness for two tip structures with three tip clearances. Applied Thermal Engineering, 2022, 202: 1–14.

    Article  Google Scholar 

Download references

Acknowledgements

The authors gratefully acknowledge the financial supports for the project from the National Science and Technology Major Project of China (2017-III-0010-0036), China Postdoctoral Science Foundation (NO.2020TQ0147) and Natural Science Foundation of Jiangsu Province (NO. BK20200454).

Author information

Authors and Affiliations

  1. Jiangsu Province Key Laboratory of Aerospace Power System, Nan**g University of Aeronautics and Astronautics, Nan**g, 210016, China

    Shuai Bi, Longfei Wang, Feilong Wang, Lei Wang & Ziqiang Li

Authors
  1. Shuai Bi
    View author publications

    You can also search for this author in PubMed Google Scholar

  2. Longfei Wang
    View author publications

    You can also search for this author in PubMed Google Scholar

  3. Feilong Wang
    View author publications

    You can also search for this author in PubMed Google Scholar

  4. Lei Wang
    View author publications

    You can also search for this author in PubMed Google Scholar

  5. Ziqiang Li
    View author publications

    You can also search for this author in PubMed Google Scholar

Corresponding author

Correspondence to Longfei Wang.

Rights and permissions

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Bi, S., Wang, L., Wang, F. et al. Effect of Squealer Tip with Deep Scale Depth on the Aero-thermodynamic Characteristics of Tip Leakage Flow. J. Therm. Sci. 31, 1773–1789 (2022). https://doi.org/10.1007/s11630-022-1683-4

Download citation

  • Received:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1007/s11630-022-1683-4

Keywords

Search

Navigation