Transactions of the Korean Society of Automotive Engineers (한국자동차공학회논문집)

The Korean Society of Automotive Engineers (한국자동차공학회)
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Cooling Heat Transfer Characteristics of Carbon Dioxide in a Horizontal and Helically Coiled Tube

수평관과 헬리컬 코일관내 이산화탄소의 냉각 열전달 특성

  • Son, Chang-Hyo (Department of Mechanical Engineering, Pukyong University)
  • 손창효 (부경대학교 기계공학부)
  • Published : 2008.02.01
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Abstract

The cooling heat transfer coefficient of $CO_2$ (R-744) in a horizontal and helically coiled tube was investigated experimentally. The main components of the refrigerant loop are a receiver, a variable-speed pump, a mass flow meter, a pre-heater, evaporator and gas cooler (test section). The test section consists of a horizontal stainless steel tube and hellically coiled copper tube of 4.57 and 7.75 mm. The experiments were conducted at saturation temperature of 100 to $20^{\circ}C$, and mass flux of 200 to $500kg/m^2s$. The test results showed the variation of the heat transfer coefficient tended to decrease as cooling pressure of $CO_2$ increased. The heat transfer coefficient with respect to mass flux increased as mass flux increased. The experimental results were also compared with the existing correlations for the supercritical heat transfer coefficient, which generally underpredicted the measured data. However, the experimental data showed a relatively good agreement with the correlations of Pitla et al. except for the pseudo critical temperature.

Keywords

References

  1. K. Mori, J. Onishi, H. Shimaoka, S. Nakanishi and H. Kimoto, "Cooling Heat Transfer Characteristics of $CO_{2}$ Oil Mixture at Supercritical Pressure Conditions," Proceedings of the Asian Conference on Refrigeration and Air Conditioning, Kobe, Japan, pp.81-86, 2002
  2. C. Dang, Cooling Heat Transfer of Supercritical Carbon Dioxide, Ph. D. Dissertation, The University of Tokyo School of Engineering Department of Mechanical Engineering, 2003
  3. J. H. Kim, An Experimental Study on Heat Transfer Characteristics during Gas Cooling Process of Carbon Dioxide, M. S. Thesis, Seoul National University, 2001
  4. B. S. Petukhove, E. A. Krasnoshchekov and V. S. Protopopov, "An Investigation of Heat Transfer to Fluids Flowing in Pipes under Supercritical Conditions," ASME International Developments in Heat Transfer Part. 3, pp.569-578, 1961
  5. E. A., Krasonshchekov, I. V. Kuraeva and V. S. Protopopov, "Local Heat Tansfer of Carbon Dioxide at Supercritical Pressure Under Cooling Conditions," Teplofizika Vysokikh Temperatur, Vol.7, No.5, pp.922-930, 1970
  6. V. L. Baskov, I. V. Kuraeva and V. S. Protopopov., "Heat Transfer with the Turbulent Flow of a Liquid at Supercritical Pressure in Tubes under Cooling Conditions," Teplofizika Vysokikh Temperatur, Vol.15, No.1, pp.96-102, 1977
  7. N. E. Petrov and V. N. Popov, "Heat Transfer and Resistance of Carbon Being Cooled in the Supercritical Region," Thermal Engineering, Vol.32, No.3, pp.131-134, 1985
  8. V. Gnielinski, "New Equation for Heat and Mass Transfer in Turbulent Pipe and Channel Flow," Int. Chem. Eng., Vol.16, pp.359-368, 1976
  9. E. A. Krasonshchekov and V. S. Protopopov, "Experimental Study of Heat Exchange in Carbon Dioxide in the Supercritical Range at High Temperature Drops," Teplofizika Vysokikh Temperatur, Vol.4, No.3, pp.389-398, 1966
  10. S. S. Pitla, D. M. Robinson, E. A. Groll and S. Ramadhyani, "Heat Transfer from Supercritical Carbon Dioxide in Tube Flow: A Critical Review, 1998," HVAC＆ Research, Vol.4, No.4, pp.281-301, 1998 https://doi.org/10.1080/10789669.1998.10391405
  11. X. Fang, C. W. Bullard and P. S. Hrnjak, "Heat Transfer and Pressure Drop of Gas Coolers," ASHRAE Transaction, Vol.107, Part 1, pp. 255-266, 2000