Journal of Mechanical Science and Technology

, Volume 32, Issue 2, pp 937–946 | Cite as

Experimental and numerical investigation on the flow and heat transfer characteristics in a tree-like branching microchannel

  • Linqi ShuiEmail author
  • Bo Huang
  • Feng Gao
  • Hongbin Rui


A T-shaped tree-like branching microchannel is designed for gas turbine blade cooling. The conjugate heat transfer characteristics of air coolant are investigated experimentally. To compare the flow and thermal performance of steam and air coolant numerically, the SSG turbulence model is adopted. The results reveal that the heat transfer coefficient is gradually increased through the whole branching microchannel. The conjugate heat transfer effects lead to a heat transfer suppression in the entrance region but an enhancement in the channel terminal region. The flow and heat transfer trend of steam and air are similar, however, compare to air, steam has a 49.2 % higher average Nusselt number and 31.8 % lower friction factor under the same inlet mass flow rate. Under a low mass flow rate condition, the steam cooling shows a smaller maximum temperature difference and better uniform cooling performance.


Gas turbine Blade cooling Tree-like branching microchannel Heat transfer Friction factor 


Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.


  1. [1]
    J. C. Han, S. Dutta and S. Ekkad, Gas turbine heat transfer and cooling technology, Taylor and Francis, New York, USA (2000).Google Scholar
  2. [2]
    R. S. Bunker, Gas turbine cooling: moving from macro to micro cooling, ASME paper No. 2013-94277 (2013).Google Scholar
  3. [3]
    G. M. Mala, D. Li and J. D. Dale, Heat transfer and fluid flow in microchannels, International Journal of Heat and Mass Transfer, 40 (13) (1999) 3079–3088.CrossRefzbMATHGoogle Scholar
  4. [4]
    T. F. Sherman, On connecting large vessels to small, he meaning of Murray's law, TThe Journal of General Physiology, 78 (4) (1981) 431–453.CrossRefGoogle Scholar
  5. [5]
    M. Neagu and A. Bejan, Constructal-theory tree networks of “constant” thermal resistance, Journal of Applied Physics, 86 (2) (1999) 1136–1144.CrossRefGoogle Scholar
  6. [6]
    A. Bejan, L. A. O. Rocha and S. Lorente, Thermodynamic optimization of geometry: T-and Y-shaped constructs of fluid streams, International Journal of Thermal Sciences, 39 (9–11) (2000) 949–960.CrossRefGoogle Scholar
  7. [7]
    G. B. West, J. H. Brown and B. J. Enquist, A general model for the structure and allometry of plant vascular systems, Nature, 400 (6745) (1999) 664–667.CrossRefGoogle Scholar
  8. [8]
    D. V. Pence, Reduced pumping power and wall temperature in microchannel heat sinks with fractal-like branching channel networks, Microscale Thermophysical Engineering, 6 (4) (2003) 319–330.CrossRefGoogle Scholar
  9. [9]
    S. M. Senn and D. Poulikakos, Laminar mixing heat transfer and pressure drop in tree-like microchannel nets and their application for thermal management in polymer electrolyte fuel cells, Journal of Power Sources, 130 (2004) 178–191.CrossRefGoogle Scholar
  10. [10]
    X. Q. Wang, A. S. Mujumdar and C. Yap, Thermal characteristics of tree-shaped microchannel nets for cooling of a rectangular heat sink, International Journal of Thermal Sciences, 45 (11) (2006) 1103–1112.CrossRefGoogle Scholar
  11. [11]
    Y. Chen and P. Cheng, Heat transfer and pressure drop in fractal tree-like microchannel nets, International Journal of Heat and Mass Transfer, 45 (13) (2002) 2643–2648.CrossRefzbMATHGoogle Scholar
  12. [12]
    Y. Chen, C. Zhang and M. Shi, Thermal and hydrodynamic characteristics of constructal tree-shaped minichannel heat sink, AIChE Journal, 56 (8) (2010) 2018–2029.Google Scholar
  13. [13]
    S. Xu, J. Qin and W. Guo, The design of an asymmetric bionic branching channel for electronic chips cooling, Heat and Mass Transfer, 49 (6) (2013) 827–834.CrossRefGoogle Scholar
  14. [14]
    S. Salakij, J. A. Liburdy and D. V. Pence, Modeling in situ vapor extraction during convective boiling in fractal-like branching microchannel networks, International Journal of Heat and Mass Transfer, 60 (2013) 700–712.CrossRefGoogle Scholar
  15. [15]
    C. Xia, J. Fu and J. Lai, Conjugate heat transfer in fractal tree-like channels network heat sink for high-speed motorized spindle cooling, Applied Thermal Engineering, 90 (2015) 1032–1042.CrossRefGoogle Scholar
  16. [16]
    L. Chen, H. Feng and Z. Xie, Thermal efficiency maximization for H-and X-shaped heat exchangers based on constructal theory, Applied Thermal Engineering, 91 (2015) 456–462.CrossRefGoogle Scholar
  17. [17]
    X. Chen, Z. Zhang and D. Yi, Numerical studies on different two-dimensional micromixers basing on a fractal-like tree network, Microsystem Technologies, 23 (3) (2017) 755–763.CrossRefGoogle Scholar
  18. [18]
    M. A. Devore and E. D. Kaufman, Branched airfoil core cooling arrangement, U.S. Patent 8449254, USA (2013).Google Scholar
  19. [19]
    F. Ahmad, T. Burzych and E. Hummel, Arrangement of cooling channels in a turbine blade, U.S. Patent 15023392, USA (2014).Google Scholar
  20. [20]
    J. N. Sun, J. Deng and H. W. Deng, Structure design of a new cooling system combined microchannel and film cooling in the turbine blade, Journal of Beijing University of Aeronautics and Astronautics, 38 (5) (2012) 702–706.Google Scholar
  21. [21]
    J. N. Zhu, T. Y. Gao and J. Li, The Effect of vortex core distribution on heat transfer in steam cooling of gas turbine blade internal ribbed channels, ASME paper No. 2014-25324 (2014).Google Scholar
  22. [22]
    Y. T. Yang, H. W. Tang and C. J. Wong, Numerical simulation and optimization of turbulent fluids in a threedimensional angled ribbed channel, Numerical Heat Transfer, Part A: Applications, 70 (5) (2016) 532–545.CrossRefGoogle Scholar
  23. [23]
    L. Q. Shui, J. M. Gao and X. J. Shi, Effect of duct aspect ratio on heat transfer and friction in steam-cooled ducts with 60 angled rib turbulators, Experimental Thermal and Fluid Science, 49 (2013) 123–134.CrossRefGoogle Scholar
  24. [24]
    C. Ma, X. L. Chen and J. F. Wang, An experimental investigation of heat transfer characteristics for steam cooling and air cooling in a rectangular channel roughened with parallel rib, Experimental Thermal and Fluid Science, 64 (2015) 142–151.CrossRefGoogle Scholar
  25. [25]
    T. Wang, J. L. Gaddis and X. Li, Mist/steam heat transfer of multiple rows of impinging jets, International Journal of Heat and Mass Transfer, 48 (25) (2005) 5179–5191.CrossRefGoogle Scholar
  26. [26]
    G. Liao, X. Wang and J. Li, A numerical comparison of thermal performance of in-line pin-fins in a wedge duct with three kinds of coolant, International Journal of Heat and Mass Transfer, 77 (2014) 1033–1042.CrossRefGoogle Scholar
  27. [27]
    C. Du, L. Li and S. Li, Effects of aerodynamic parameters on steam vortex cooling behavior for gas turbine blade leading edge, Proceedings of the Institution of Mechanical Engineers, Part A: Journal of Power and Energy, 230 (4) (2016) 354–365.Google Scholar
  28. [28]
    B. B. Mandelbrot and R. Pignoni, The fractal geometry of nature, WH freeman, New York, USA (1983).Google Scholar
  29. [29]
    P. Xu and B. Yu, The scaling laws of transport properties for fractal-like tree networks, Journal of Applied Physics, 100 (10) (2006) 104906.CrossRefGoogle Scholar
  30. [30]
    S. J. Kline and F. A. McClintock, Describing experimental uncertainties in single-sample experiments, Mechanical Engineering, 75 (1) (1953) 3–8.Google Scholar
  31. [31]
    C. Nonino, S. Savino and S. Del Giudice, Conjugate forced convection and heat conduction in circular microchannels, International Journal of Heat and Fluid Flow, 30 (5) (2009) 823–830.CrossRefGoogle Scholar
  32. [32]
    K. Stephan and P. Preußer, Wärmeübergang und maximale wärmestromdichte beim behältersieden binärer und ternärer flüssigkeitsgemische, Chemie Ingenieur Technik, 51 (1) (1979) 37–37.CrossRefGoogle Scholar
  33. [33]
    R. K. Shah and A. L. London, Laminar flow forced convection in ducts, Journal of Fluids Engineering, 102 (2) (1978) 431–455.Google Scholar
  34. [34]
    F. P. Incropera and D. P. De Witt, Fundamentals of heat and mass transfer, Second Ed., Wiley, New York, USA (2007).Google Scholar
  35. [35]
    S. Kakac, R. K. Shah and W. Aung, Handbook of singlephase convective heat transfer, John Wiley and Sons, New York (1987).Google Scholar

Copyright information

© The Korean Society of Mechanical Engineers and Springer-Verlag GmbH Germany, part of Springer Nature 2018

Authors and Affiliations

  1. 1.Key Lab of NC Machine Tools and Integrated Manufacturing Equipment of the Education Ministry & Key Lab of Manufacturing Equipment of Shaanxi ProvinceXi’an University of TechnologyXi’anChina

Personalised recommendations