Korean Journal of Air-Conditioning and Refrigeration Engineering (설비공학논문집)

The Society of Air-Conditioning and Refrigerating Engineers of Korea (대한설비공학회)
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Correlations of Oil Concentration Prediction during In-line Flow of $CO_2/Oil$ Mixtures

유동중인 $CO_2$냉매와 오일 혼합물의 농도 예측을 위한 상관식

  • Park, Keun-Seo (Graduate school, Kookmin University) ;
  • Kang, Byung-Ha (School of Mechanical and Automative Engineering, Kookmin University) ;
  • Park, Kyoung-Kuhn (School of Mechanical and Automative Engineering, Kookmin University) ;
  • Kim, Suk-Hyun (School of Mechanical and Automative Engineering, Kookmin University)
  • 박근서 (국민대학교 대학원) ;
  • 강병하 (국민대학교 기계.자동차공학부) ;
  • 박경근 (국민대학교 기계.자동차공학부) ;
  • 김석현 (국민대학교 기계.자동차공학부)
  • Published : 2007.10.10
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Abstract

In the general vapor-compression refrigeration system, refrigeration lubricant circulates in refrigeration system with refrigerant. Knowledge of the amount of circulating lubricant is very important to exactly calculate capacity of the refrigeration system. An experimental study was conducted to estimate the oil concentration of a flowing $CO_2/Oil$ mixtures. POE and PAG oil are considered as test lubricants in this study. Performance tests were conducted under simulated liquid conditions for $CO_2/POE$ oil mixture in oil concentration of 0 to 10 weight-percent and $CO_2/PAG$ oil mixture in oil concentration of 0 to 6 weight-percent in the temperature ranges of $-5^{\circ}C\;to\;15^{\circ}C$. The results obtained indicate specific gravity of $CO_2/Oil$ mixture is increased as oil concentration is increased and as temperature of mixture is decreased. Oil concentration correlation of $CO_2/POE$ oil mixture and $CO_2/PAG$ oil mixture is suggested, based on the measurement of specific gravity and temperature. This correlation enable to predict the oil concentration without extraction of the mixture and can be applied for $CO_2/POE$ mixtures and $CO_2/PAG$ mixtures.

Keywords

References

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