Optimizing energy consumption in air conditioning system and refrigerator in residential buildings using ground energy

Document Type : Original Article

Authors

1 MSc student, Department of Mechanical Engineering, Qom University of Technology, Qom, Iran.

2 Assistant Professor, Department of Mechanical Engineering, Qom University of Technology, Qom, Iran.

Abstract

In order to reduce energy consumption in air conditioning and refrigeration systems, in this research, a system based on the vapor compression refrigeration cycle and ground energy use has been proposed. This system centrally supplies the energy needed for the air conditioning unit, refrigerator and freezer of a building. The condensing unit of this system is cooled separately and in series by two heat exchangers using outdoor air as well as ground energy. The energy consumption for a sample building is simulated by analytical calculations as well as the use of HYSSIS and TRANSYS softwares. The results of the calculations, which include the system performance coefficient, compressor power consumption, refrigerant quality and mass flow rate, have been compared with the values ​​of the conventional system. The results show that using the water cooled condenser unit, the inlet refrigerant temperature to the reducer valve is significantly lower than the outdoor air temperature. This significantly increases the performance of the proposed system and significantly reduces the refrigerant mass flow rate. The effect of reducing the exit refrigerant temperature of the condensing unit on the exergy of the refrigerant has also been investigated.

Keywords


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