Skip to main content
SpringerLink
Log in

Measurement of heat/mass transfer at second stage vane endwall according to step heights

  • Original Article
  • Published:
Journal of Mechanical Science and Technology Aims and scope Submit manuscript

Abstract

Recently, domestic gas turbines are primarily operated under partial loads. Hence, thermal expansion of components decreases, leading to a discontinuity between the 1st blade and 2nd vane. In this study, the local heat transfer coefficients are derived using the naphthalene sublimation method to analyze thermal characteristics based on step height, and flow characteristics are analyzed using numerical simulation. An extreme heat load of the flat endwall appears around the leading edge of the vane due to the secondary vortex. Under the step conditions, the heat load increases in the upstream region as the main flow near the endwall is reattached to the endwall surface. In addition, two high heat transfer distributions appear due to the recirculation flow, and a step-induced vortex is formed. As the step-induced vortex moves to the suction side within the vane flow path, a high thermal load appears in the corresponding region. Consequently, we found that the occurrence of a step causes severe thermal damage in the upstream region of the vane endwall. The area-averaged heat transfer of the stepped endwall is increased by about 10.6 % and 17.3 % at hs/Cx = 0.05 and 0.1, respectively, as compared to that of the flat endwall.

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

Access this article

Log in via an institution

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Institutional subscriptions

Similar content being viewed by others

Abbreviations

A :

Area [m2]

C p :

Pressure coefficient \(\left(\frac{p_{s}-p_{s,\infty}}{0.5\rho U_{\infty}^{2}}\right)\)

C :

Chord length [m]

C x :

Axial chord length [m]

DTKE :

Dimensionless turbulence kinetic energy (TKE/Uout2)

D naph :

Mass diffusion coefficient of naphthalene vapor in air [m2/s]

h :

Heat transfer coefficient [W/m2 · K]

h m :

Mass transfer coefficient [m/s]

h s :

Step height [m]

\(\dot{m}\) :

Local naphthalene mass transfer rate per unit area [kg/m2s]

P :

Pitch [mm]

Pr :

Prandtl number (μCp/k)

Re :

Reynolds number (U∞ · Cx/v)

S:

Span height [mm]

Sc :

Schmidt number (v/Dnaph)

Sh:

Sherwood number (hm · Cx/Dnaph)

\(\overline{\underline{\underline{Sh}}}\) :

Pitchwise line averaged Sherwood number

Sh :

Area-averaged Sherwood number

TKE :

Turbulence kinetic energy [m2/s2]

U ∞ :

Mass-averaged mainstream velocity of inlet [m/s]

x :

Streamwise direction

y :

Spanwise direction

z :

Pitchwise direction

β 1 :

Inlet flow angle [°]

β 2 :

Outlet flow angle [°]

ρ :

Fluid density [kg/m3]

ρ s :

Density of solid naphthalene [kg/m3]

ρ v,w :

Naphthalene vapor density on the surface [kg/m3]

ρ v,∞ :

Naphthalene vapor density at approaching flow [kg/m3]

References

  1. L. S. Langston, Secondary flows in axial turbines-a review, Annals New York Academy of Science, 934 (2001) 11–26.

    Article  Google Scholar 

  2. R. J. Goldstein, H. P. Wang and M. Y. Jabbari, The influence of secondary flows near the endwall and boundary layer disturbance on convective transport from a turbine blade, Journal of Turbomachinery, 117 (1995) 657–665.

    Article  Google Scholar 

  3. S. Friedrichs, H. P. Hodson and W. N. Dawes, Heat transfer committee best paper of 1995 award: distribution of film-cooling effectiveness on a turbine endwall measured using the ammonia and diazo technique, Journal of Turbomachinery, 118 (1996) 613–621.

    Article  Google Scholar 

  4. J. Cho, K. Kim, J. Kim and E. Jeong, Controlling the secondary flows near endwall boundary layer fences in a 90 turning duct using approximate optimization method, Journal of Mechanical Science and Technology, 25(8) (2011) 2025.

    Article  Google Scholar 

  5. H. P. Wang, S. J. Olson, R. J. Goldstein and E. R. G. Eckert, Flow visualization in a linear turbine cascade of high performance turbine blades, Journal of Turbomachinery, 119 (1997) 1–8.

    Article  Google Scholar 

  6. W. G. W. Aizon, K. Funazaki and T. Miura, Purge flow effect on aerodynamics performance in high-pressure turbine cascade, Journal of Mechanical Science and Technology, 27(6) (2013) 1611–1617.

    Article  Google Scholar 

  7. M. K. Chyu, Heat transfer near turbine nozzle endwall, Annals New York Academy of Science, 934 (2001) 27–36.

    Article  Google Scholar 

  8. T. W. Simon and J. D. Piggush, Turbine endwall aerodynamics and heat transfer, Journal of Propulsion and Power, 22 (2006) 301–312.

    Article  Google Scholar 

  9. X. Yang, Z. Liu, Q. Zhao, Z. Liu, Z. Feng, F. Guo, L. Ding and T. W. Simon, Experimental and numerical investigations of overall cooling effectiveness on a vane endwall with jet impingement and film cooling, Applied Thermal Engineering, 148 (2019) 1148–1163.

    Article  Google Scholar 

  10. M. B. Kang, A. Kohli and K. A. Thole, Heat transfer and flowfield measurements in the leading edge region of a stator vane endwall, Journal of Turbomachinery, 121 (1999) 558–568.

    Article  Google Scholar 

  11. R. W. Radomsky and K. A. Thole, High free-steam turbulence effects on endwall heat transfer for a gas turbine stator vane, Journal of Turbomachinery, 122 (2000) 699–708.

    Article  Google Scholar 

  12. S. Park, H.-S. Sohn, H. H. Cho, H. K. Moon, Y. S. Han and O. Ueda, Effects of wakes on blade endwall heat transfer in high turbulence intensity, Journal of Turbomachinery, 142 (2020) 021002.

    Article  Google Scholar 

  13. S. M. Choi, J. Kim, M. Bang, J. Kim and H. H. Cho, Effect of the wake on the heat transfer of a turbine blade endwall according to relative position of the cylindrical rod, International Communications in Heat and Mass Transfer, 94 (2018) 61–70.

    Article  Google Scholar 

  14. J. S. Park, E. Y. Jung, D. H. Lee, K. M. Kim, B. S. Kim, B. M. Chang and H. H. Cho, Effects of unsteady wake on heat transfer of endwall surface in linear cascade, Journal of Heat Transfer, 136 (2014) 061701.

    Article  Google Scholar 

  15. S. M. Choi, J. S. Park, H. Chung, S. Park and H. H. Cho, Upstream wake effect on flow and heat transfer characteristics at an endwall of first-stage blade of a gas turbine, Experimental Thermal and Fluid Science, 86 (2017) 23–36.

    Article  Google Scholar 

  16. E. de la Rosan Balnco, H. P. Hodson and R. Vazquez, Effect of upstream platform geometry on the endwall flows of a turbine cascade, Turbo Expo: Power for Land, Sea, and Air, 47306 (2005) 1–11.

    Google Scholar 

  17. W. F. Colban, K. A. Thole and G. Zess, Combustor turbine interface studies, part 1: endwall effectiveness measurements, Journal of Turbomachinery, 125 (2003) 193–202.

    Article  Google Scholar 

  18. J. D. Piggush and T. W. Simon, Heat transfer measurements in a first-stage nozzle cascade having endwall contouring: misalignment and leakage studies, Journal of Turbomachinery, 129 (2007) 782–790.

    Article  Google Scholar 

  19. L. Zhang and H. K. Moon, Turbine nozzle endwall inlet film cooling: the effect of a back-facing step, Turbo Expo 2003, Parts A and B, ASMEDC, 5 (2003) 203–211.

    Google Scholar 

  20. J. Kim, H.-S. Sohn, S. Choi, W.-T. Hsu, O. Ueda and H. H. Cho, Effect of misalignment at 2nd vane endwall on heat transfer with purge flow, International Journal of Heat and Mass Transfer, 170 (2021) 121034.

    Article  Google Scholar 

  21. H. H. Cho and R. J. Goldstein, Heat (mass) transfer and film cooling effectiveness with injection through discrete holes: part I-within holes and on the back surface, Journal of Turbomachinery, 117 (1995) 440–450.

    Article  Google Scholar 

  22. D. Ambrose, I. J. Lawrenson and C. H. S. Sprake, The vapour pressure of naphthalene, The Journal of Chemical Thermodynamics, 7 (1975) 1173–1176.

    Article  Google Scholar 

  23. H. Chung, C. W. Hong, S. H. Kim, H. H. Cho and H. K. Moon, Heat transfer measurement near endwall region of first stage gas turbine nozzle having platform misalignment at combustorturbine interface, International Communications in Heat and Mass Transfer, 78 (2016) 101–111.

    Article  Google Scholar 

Download references

Acknowledgments

This work was supported by the Human Resources Development program (No.20204030200110) of the Korea Institute of Energy Technology Evaluation and Planning (KETEP) grant funded by the Korea government Ministry of Trade, Industry and Energy. In addition, the authors wish to acknowledge support for this study by Mitsubishi Power, Ltd.

Author information

Author notes

  1. These authors equally contributed to this work as first author.

Authors and Affiliations

  1. Department of Mechanical Engineering, Yonsei University, Seoul, 03722, Korea

    JeongJu Kim, Ho-Seong Sohn, Hee Seung Park, Wei-Ting Hsu & Hyung Hee Cho

  2. Takasago Service Sales and Strategic Planning Department, Takasago Service Division, Mitsubishi Power, Ltd., Takasago, Japan

    Osamnu Ueda

Authors
  1. JeongJu Kim
    View author publications

    You can also search for this author in PubMed Google Scholar

  2. Ho-Seong Sohn
    View author publications

    You can also search for this author in PubMed Google Scholar

  3. Hee Seung Park
    View author publications

    You can also search for this author in PubMed Google Scholar

  4. Wei-Ting Hsu
    View author publications

    You can also search for this author in PubMed Google Scholar

  5. Osamnu Ueda
    View author publications

    You can also search for this author in PubMed Google Scholar

  6. Hyung Hee Cho
    View author publications

    You can also search for this author in PubMed Google Scholar

Corresponding author

Correspondence to Hyung Hee Cho.

Additional information

JeongJu Kim received his B.S. degree in Mechanical Engineering from Chung Ang University and is currently a Ph.D. candidate in Department of Mechanical Engineering at Yonsei University. His research interests include heat transfer in cooling of the gas turbine.

Ho-Seong Sohn received his B.S. degree in Mechanical Engineering from Yonsei University and is currently a Ph.D. candidate in Department of Mechanical Engineering at Yonsei University. His research interests include heat transfer in cooling of the gas turbine.

Hee Seung Park received his B.S. degree in Mechanical Engineering from Yonsei University and is currently a Ph.D. candidate in Department of Mechanical Engineering at Yonsei University. His research interests include heat transfer in cooling of the gas turbine.

Wei-Ting Hsu received his M.S. degree in Mechanical Engineering from Chienkuo Technology University, Taiwan, and is currently a Ph.D. candidate in Department of Mechanical Engineering at Yonsei University. His research interests include heat transfer in cooling technologies.

Osamu Ueda received his M. S. degree in Mechanical Engineering from Gifu University and worked on the development of large gas turbines at Mitsubishi Power Corporation since 1995. Specialized in heat transfer engineering, structural strength, materials and metallurgy for gas turbine blades. He belongs to the Japan Society of Mechanical Engineers (JSME) and the Japan Gas Turbine Society.

Hyung Hee Cho received his Ph.D. degree in Mechanical Engineering from the University of Minnesota in 1992. He is currently a Professor at Department of Mechanical Engineering at Yonsei University. He is a fellow of the American Society of Mechanical Engineers and senior member of the National Academy of Engineering of Korea.

Rights and permissions

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Kim, J., Sohn, HS., Park, H.S. et al. Measurement of heat/mass transfer at second stage vane endwall according to step heights. J Mech Sci Technol 35, 4575–4583 (2021). https://doi.org/10.1007/s12206-021-0927-z

Download citation

  • Received:

  • Revised:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1007/s12206-021-0927-z

Keywords

Search

Navigation