International Journal of Air-Conditioning and Refrigeration

The Society of Air-Conditioning and Refrigerating Engineers of Korea (대한설비공학회)
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Modelling of a High Efficiency Refrigeration System with Heat Storage for Reverse Cycle Hot Gas Defrost

  • Ardiyansyah, Ardiyansyah (Graduate School, Chonnam National University) ;
  • Choi, Kwang-Il (Graduate School, Chonnam National University) ;
  • Oh, Jong-Taek (Dept. of Refrigeration and Air Conditioning Eng., Chonnam National University) ;
  • Oh, Hoo-Kyu (Dept. of Refrigeration and Air Conditioning Eng., Pukyong National University)
  • Published : 2007.12.30
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Abstract

A computer model of a high efficiency refrigeration system equipped with heat storage for reverse cycle-hot gas defrost (the stored heat is used during defrost cycle of the system) is presented. The model was developed based on both theoretical and empirical equations for the compressor, evaporator, condenser and the heat storage equipment. Simulations of the prototype system were carried out to investigate refrigeration system performance under various operating conditions during refrigeration cycles. The simulations of the evaporator during defrost cycles at 30 and $40^{\circ}C$ hot gas refrigerant temperature were also performed which resulted on shorter defrost time but only slight increase in defrost efficiency. These information on energy efficiency and the defrost time required are important in order to avoid excessive parasitic load and temperature rise of the refrigerated room.

Keywords

References

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