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Cooling Heat Transfer Characteristics of CO2 in a Brazing Type Small Diameter Copper Tube

브레이징식 동세관내 CO2의 냉각 열전달 특성

  • 오후규 (부경대학교 기계공학부 냉동공조공학과) ;
  • 손창효 (부경대학교 기계공학부)
  • Published : 2009.09.30

Abstract

The cooling heat transfer coefficient of $CO_2$ in a brazing type small diameter tube was investigated experimentally. The main components of the refrigerant loop are a receiver, a $CO_2$ compressor, a mass flow meter, an evaporator and a brazing type small diameter tube as a test section. The mass flux of $CO_2$ is $400{\sim}1600$ [kg/$m^2s$], the mass flowrate of coolant were varied from 0.15 to 0.3 [kg/s], and the cooling pressure of gas cooler were from 8 to 10 [MPa]. The cooling heat transfer coefficients of the brazing type small diameter copper tube is about $4{\sim}11.7%$ higher than that of the conventional type small diameter copper tube. In comparison with test results and existing correlations, correlations failed to predict the cooling heat transfer coefficient of $CO_2$ in a brazing type small diameter copper tube. therefore, it is necessary to develope reliable and accurate predictions determining the cooling heat transfer coefficient of $CO_2$ in a brazing type small diameter copper tube.

Keywords

References

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