Comparison of exergy and thermoeconomic analysis for variable refrigerant flow (vrf) system with different rerigerants

Nowadays lots of heating and cooling systems are available. Variable Refrigerant Flow System is one of these systems. These systems can be used both as a cooling system and a heat pump. Due to said functionally, these systems distinguish in the buildings which need different air conditions in the same time like hotels, schools or hospitals. Furthermore, with the capability of heating and cooling at the same time, these systems contribute to energy conservation. Another important advantage of these systems is that with one outside unit, more than one inside unit can be work. In this study, exergy losses and entropy generations of variable refrigerant flow (VRF) system has been evaluted in different working condition, mass flow rates and refrigerants. Exergy efficiencies that occur as a result of these losses has been determined. Besides, thermoeconomic analysis of system after the exergy analysis and cost calculation which considered exergy have been carried out. With this study, optimum working contidions of VRF systems and refrigerants that has provided minimum exergy losses have been determined. Cost of the system according to exergy has been evaluated considering working conditions and refrigerants. According to analysis it is explained that, the condition in which VRF system heating and cooling simultaneously, is the most efficient working condition. Also the effects of refrigerants and mass flow rate of refrigerant to exergy efficiency and cost of the system according to exergy has been revealed.