THERMAL SCIENCE

International Scientific Journal

Thermal Science - Online First

Authors of this Paper

External Links

online first only

Boiling-condensation heat transfer and flow characteristics in ultrathin limited enclosed space based on numerical simulation and visualization experiment

ABSTRACT
Boiling-condensation heat transfer in ultrathin flat heat pipes are complicated and difficult to observe. In this study, a visualization experiment and simulation analysis in an ultrathin limited enclosed space were carried out. Width of the ultrathin enclosed space was 1 mm, with anhydrous ethanol as the working medium. The enclosed space was oriented vertically with the heating section on the bottom and the cooling section on the top. Flow characteristics of the anhydrous ethanol were photographed using a high-speed camera through the quartz cover. The boiling-condensation heat transfer and fluid flow in the limited enclosed space were simulated. Effective heat transfer coefficient calculated based on the experimental data varied from 1.0 to 1.1 W/°C, while that of the inner wall obtained by the simulation varied within the range of 1.068-1.076 W/°C. The maximum error was 2.9%, which verified the reliability of the simulation results. By analyzing the pressure change in condensation section, it was found that the boiling-condensation heat released in the enclosed space changed periodically, because of the growth and bursting of bubbles and falling of the working medium due to gravity. Restricted by the thickness, the bubbles produced by boiling of the working medium grew in flat and irregular shapes, promoting the upward movement of the rest of the liquid working medium, and a liquid film was formed at the heated inner surface for evaporation heat transfer, which enhanced the heat transfer capacity of the heating section.
KEYWORDS
PAPER SUBMITTED: 2021-06-22
PAPER REVISED: 2021-10-27
PAPER ACCEPTED: 2021-10-29
PUBLISHED ONLINE: 2022-01-02
DOI REFERENCE: https://doi.org/10.2298/TSCI210622348C
REFERENCES
  1. T. Yong, T. Heng, W. Zhenping, Y. Wei, Development Status and Perspective Trend of Ultra thin Micro Heat Pipe, JOURNAL OF MECHANICAL ENGINEERING , 53(20) (2017) 131 144.
  2. L. Jiang, Y. Tang, M. Pan, W. Zhou, L. Lu, Phase change flattening process for axial grooved heat pipe, Journal Of Materials Processing Technology , 212(1) (2012) 331 338.
  3. E. Ishibashi, K. Nishikawa, Saturated boiling heat transfer in narrow spaces, International Journal of Heat and Mass Transfer , 12(8) (1969) 863 893.
  4. J. Bonjour, M. Lallemand, Flow patterns during boiling in a narrow space between two vertical surfaces, International Journal of Multiphase Flow , 24(6) (1998) 947 960.
  5. Y. Fujita, H. Ohta, S. Uchida, K. Nishikawa, Nucleate boiling heat transfer and critical he at flux in narrow space between rectangular surfaces, International Journal of Heat and Mass Transfer , 31(2) (1988) 229 239.
  6. M. Misale, G. Guglielmini, A. Priarone, HFE 7100 pool boiling heat transfer and critical heat flux in inclined narrow spaces, International Journal of Refrigeration , 32(2) (2009) 235 245.
  7. L. Lu, H. Liao, X. Liu, Y. Tang, Numerical analysis on thermal hydraulic performance of a flat plate heat pipe with wick column, Heat And Mass Transfer , 51(8) (2015) 1051 1059.
  8. G. Zhang, Z. Liu, C. Wang, An experimental study of boiling and condensation co existing phase change heat transfer in small confined space, International Journal Of Heat And Mass Transfer , 64 (2013) 1082 1090.
  9. G. Zhang, Z. Liu, C. Wang, A visualization study of the influences of liquid levels on boiling and condensation co existing phase change heat transfer phenomenon in small confined spaces, International Journal Of Heat And Mass Transfer , 73 (2014) 415 423.
  10. G. Xia, W. Wang, L. Cheng, D. Ma, Visualization study on the instabilities of phase change heat transfer in a flat two phase closed thermosyphon, Applied Thermal Engineering , 116 (2017) 392 405.
  11. L. Wu, Y. Chen, S. Wu, M. Zhang, W. Yang, F. Tang, Visualization Study of Startup Modes and Operating States of a Flat Two Phase Micro Thermosyphon, Energies , 11(9) (
  12. Z. Deng, Y. Zheng, X. Liu, B. Zhu, Y. Chen, Experimental study on thermal performance of an anti gravity pulsating heat pipe and its application on heat recovery utilization, Applied Thermal Engineering , 125 (2017) 1368 1378.
  13. H.J. Kim, S. H. Lee, S.B. Kim, S.P. Jang, The effect of nanoparticle shape on the thermal resistance of a flat plate heat pipe using acetone based Al2O3 nanofluids, International Journal Of Heat And Mass Transfer , 92 (2016) 572 577.
  14. N. Blet, S. Lips, V. Sartre, Heats pipes for temperature homogenization: A literature review, Applied Thermal Engineering, 118 (2017) 490 509.
  15. K.H. Do, S.J. Kim, S.V. Garimella, A mathematical model for analyzing the thermal characteristics of a flat micro heat pipe with a grooved wick, International Journal Of Heat And Mass Transfer , 51(19 20) (2008) 4637 4650.
  16. Q. Jian, C. Li, L. Wang, ANALYSIS ON THERMAL AND HYDRAULIC PERFORMANCE OF A T SHAPED VAPOR CHAMBER DESIGNED FOR MOTORCYCLE LED LIGHTS, Thermal Science, 23(1) (2019) 137 148.
  17. L. Tanya, S. Lingamneni, J. Palko, M. Asheghi, K.E. Goodson, Optimization of hybrid wick structures for extreme spreading in high performance vapor chambers, in: 2016 15th IEEE Intersociety Conference on Thermal and Thermomechanical Phenomena in Electronic Systems (ITherm), 2016, pp. 30 36.
  18. J.U. Brackbill, D.B. Kothe, C. Zemach, A continuum method for modeling surface tension, Journal of Computational Physics , 100(2) (1992) 335 354.
  19. X. Wang, Y. Zhu, Y. Wang, Development of pressure based phase change model for CFD modelling of heat pipes, International Journal of Heat and Mass Transfer , 145 (2019)
  20. D.A. Reay, P.A. Kew, R.J. McGlen, Chapter 2 Heat transfer and fluid flow theory, in: D.A. Reay, P.A. Kew, R.J. McGlen (Eds.) Heat Pipes (Sixth Edition), Butterworth Heinemann, Oxford, 2014, pp. 15 64.
  21. Y. Katto, S. Yokoya, K. Teraoka, Nucleate and Transition Boiling in a Narrow Space between Two Horizontal, Parallel Disk Surfaces, Bulletin of JSME, 20(143) (1977) 638 643.