Heat Transfer Correlation during Gas-Cooling Process of Carbon Dioxide in a Horizontal Tube

  • Kang Byung-Ha (School of Mechanical and Automative Engineering, Kookmin University) ;
  • Choi Yi-Cheol (Graduate School, Kookmin University) ;
  • Kim Suk-Hyun (School of Mechanical and Automative Engineering, Kookmin University)
  • Published : 2006.03.01

Abstract

The characteristics of heat transfer and pressure drop have been investigated experimentally during gas-cooling process of carbon dioxide. The results of this study are useful information in the design of a heat exchanger of $CO_2$ refrigerator. The test section consists of 6 series of copper tube, 4.15 and 2.18mm ID, respectively. The inlet temperature, the operating pressure, and the mass flux are varied in the range of $80{\sim}120^{\circ}C,\;{7\sim}10MPa,\;and\;400{\sim}1,900kg/m^2s$, respectively. The heat transfer coefficient of $CO_2$ is affected by temperature, inlet pressure, and mass flux of $CO_2$. At the maximum HTC, the temperature of $CO_2$ nearly accords with the psuedocritical temperature. It is found that the pressure drop is substantially affected by mass flux and inlet pressure of $CO_2$ . The results have been compared with those of previous work. The heat transfer correlation at the gas-cooling process has been also suggested which predicts within the error of 20%.

Keywords

References

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