Thermodynamic analysis of a heat pump for different refrigerants

Abstract

ın this study, the air to air heat pump that was installed to a room having dimensions of 6000x4000x3800 mm, was tested between the outdoor temperatures of -5°C and 5°C for different refrigerants , namely R134a, R404A, R407C and R410A. The electric power drawn by the compressor, indoor unit and outdoor unit fans, temperatures and pressures at the state points were measured. Experiments at the same outdoor temperatures were repeated three times under the controlled conditions. Analyses of the results obtained from the experiments were carried out by the computer code that was developed by means of Engineering Equation Solver EES-V9.172-3D . The power consumed by the compressor, heating capacity of indoor unit, the absorbing heat capacity of outdoor unit, coefficient of performance of the heat pump, suction and discharge pressures of the compressor were investigated according to the outdoor temperatures. As the outdoor air temperature increased, the power consumed by the compressor increased whereas the indoor unit and outdoor unit capacities and coefficient of performance of the heat pump decreased on average. R134a is the most favourable refrigerants among the refrigerants under study due to consuming the least compressor power and having the highest coefficient of performance

Keywords

• Refrigeration,Heat Pump,Performance,Energy Analysis

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