Theoretical Study on Heat Exchanger Performance of a Fin-tube Evaporator with Frost Growth in a $CO_2$ Refrigerator Truck

이산화탄소 냉매를 이용한 냉동탑차용 핀-관 증발기의 서리성장에 따른 열교환기 성능에 관한 해석적 연구

  • Myung, Chi-Wook (Department of Mechanical Engineering, Graduate school of Chosun University) ;
  • Cho, Hong-Hyun (Department mechanical engineering, Chosun University)
  • 명치욱 (조선대학교 기계공학과 대학원) ;
  • 조홍현 (조선대학교 기계공학과)
  • Received : 2012.04.30
  • Accepted : 2012.05.16
  • Published : 2012.06.01

Abstract

To analyze the cooling performance of fin-tube evaporator in the refrigerator truck using R744 according to frost growth, the analytical model of evaporator was developed under frost and non-frost conditions. The performance of fin-tube evaporator was investigated with frost thickness and indoor temperature. Besides, the performance of evaporator under frost condition was compared to that under non-frost condition. As a result, area of air passage and system performance were decreased as the frost thickness increased. The cooling capacity was reduced by 10%, 20%, 30% when the frost thickness was 0.7 mm, 1.1 mm, and 1.6 mm respectively. At these conditions, the block ratio was 31%, 48%, and 71%. In addition, the outlet quality of refrigerant was not over 1 when the frost thickness was 1.6 mm in spite of high indoor air temperature.

Keywords

References

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