DOI QR코드

DOI QR Code

Visualization of Flow Characteristics on Thermosyphon with Immiscible Binary Working Fluid

비 혼합 2유체 열사이폰의 유동 특성에 관한 가시적 연구

  • 도선엽 (한국산업기술대학교 기계공학과) ;
  • 강환국 (동은에이티이에스) ;
  • 박승철 (한국산업기술대학교 기계공학과)
  • Received : 2015.04.02
  • Accepted : 2015.05.07
  • Published : 2015.05.31

Abstract

This study presents experiments to visualize the internal flow and heat transfer characteristics of thermosyphon with immiscible of water-FC40 adopted as binary working fluid. Three different regimes depending on the amount of heat flux applied to the thermosyphon were observed: natural convection, pulse boiling, and continuous boiling. Boiling incipience took place in water, which has lower vapor pressure than FC40. During natural convection water was vaporized in liquid pool while liquid film flows were formed. On the other hand, meanwhile bubbles were generated in the liquid pool during pulse and continuous boiling, the binary working fluid of water-FC40 was observed as the mixture throughout a whole range of the thermosyphon.

본 연구에서는 물과 비 혼합 비 공비 물질을 작동 유체로 사용하는 가시화 실험 장치를 제작하여 열유속을 증가시키며 시간에 따른 벽면온도 특성과 내부 유동를 카메라로 연속 촬영하며 2유체 열사이폰의 내부의 유동 및 열전달 특성에 대하여 가시적 방법으로 실험을 수행하여 실험 결과로부터 다음과 같은 결론을 얻을 수 있었다. 물과 FC40을 사용한 비 혼합 2유체 열사이폰은 열유속의 크기에 따라 자연대류, 펄스비등, 연속비등의 세가지 영역으로 구분 되었으며 비등은 증기압이 낮은 물에서 발생하였다. 자연대류에서는 액체 풀에서 물의 증발과 대류 액막 유동이 발생하였다. 액체 풀에서 비등이 발생할 때에는 강한 비등에 의하여 FC40과 물의 혼합된 상태로 전 영역에 걸쳐 기-액 이상 유동이 발생하였다.

Keywords

References

  1. H. K. Kang, "Performance Test for the Performance Reliability of the Heat Pipe for Cooling PowerSemiconductors", The Korean Institute of Power Electronics, Vol. 9, No. 3,pp. 203-212, 2004.
  2. S. E. Hong, H. K. Kang, K. C. Cho, "A Study on the Characteristics of a FrozenStart up fora Variable Conductance HeatPipe", Korean Air-Conditioning and RefrigerationEngineering of Summer Conference,pp. 339-345, 2006.
  3. E. G. Jung, H. B. J, H. Y. Kwak, "Performance Characteristics of a Heat Pipe Having Water-Ethanol Mixture as Working Fluid for Evacuated Solar Collectors", Journal of Korean Solar Energy Society, Vol 28, No 5, pp.1598-6411, 2008.
  4. H. K. Kang, W. Cho, "A Study on the Operaional Characteristics of the VCHP", Jou. of Korean Soc. of Mechanical Technology, Vol. 11, No. 4, pp. 37-43, 2009. DOI: http://dx.doi.org/10.17958/ksmt.11.4.200912.37
  5. H. K. Kang, W. Cho, "A Study on the Operational Characteristics of the Power Semiconductor Cooling Device for Frozen Start-up Using VCHP", Jou. of Korean Soc. of Mechanical Technology, Vol. 12, No. 4, pp. 211-217, 2010. DOI: http://dx.doi.org/10.17958/ksmt.12.4.201012.211
  6. S. Y. Do, H. K. Kang, S. C. Park, "A Study on the Frozen Start up Characteristics of the Immiscible Two Fluids Thermosyphon" Jou. of Korean Soc. of Mechanical Technology, Vol. 17, No. 2, pp. 223-229, 2015. https://doi.org/10.17958/ksmt.17.2.201504.223
  7. T. S. Jung, H. K. Kang, "Experimental Study on Heat Transfer Characteristics of Binary Working Fluid for Clean Large Cauldron Using Liquid-Vapor Phase Change Heat", Trans. Korean Soc. Mech. Eng. B, Vol. 38, No. 11, pp. 899-905, 2014. DOI: http://dx.doi.org/10.3795/KSME-B.2014.38.11.899
  8. C. J. Kim, S. H. Moon, H. K. Kang, "A Study on the Pulse Boiling Occuring Inside the Liquid Pool of Closed Tow-Phase Thermosyphon", Jou. of Korean Soc. of Mechanical Technology(B), Vol. 21, No. 10, PP. 1254-1261, 1997.
  9. H. K. Kang, H. S. Chung, M. S. Kim, S. S. Kim, "Flow Visualization of FC-72 Thermosyphon", Korean Air-Conditioning and Refrigeration Engineering of Summer Conference, pp. 1447-1451, 2001.
  10. H. K. Kang, J. M. Park, C. J. Kim, K. B. Yim, "An Experimental Study on the Regimes of Unstable Nucleate Boiling for a Closed Tow-Phase Thermosyphon", Korean Air-Conditioning and Refrigeration Engineering of Winter Conference, pp. 17-21, 1995.
  11. J. F. Lin, J. C. Y.Wang, "On the Pulse Boilling Frequency in Thermosypons", Int. J. Heat Transfer, Vol. 114, pp. 290-292, 1922.
  12. K. Negishi, K. Kaneko, F. Kusumoto, " Analysis of Pulsation in Two-Phase Thermosypons", Pro. 6th Iit. Heat Pipe Conf, Grenoble, pp. 436-440, 1987.
  13. H. K. Kang, " A Study on the Boiling Mechanism and Heat Transfer Characteristics of Pulse Boiling for a Closed Two-Phase Thermosyphon", Sungkyunkwan University Ph.D thesis, pp. 94-99, 1996.