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Component of vapor-compression refrigeration cycle was modeled at steady state condition. Then, modeling and simulation of the whole cycle was performed to predict system parameters such as compressor work, cooling effect and coefficient of performance (COP) in various ambient conditions. The simulation results were compared with experimental results obtained from an experimental investigation on a split-type air conditioner. It was found that the experimental and simulation results are in good agreement and the model can predict the performance of the cycle successfully. Average difference between experimental and simulation results for prediction of COP was 4.5%. Simulation results show that for each 1℃ increase in ambient temperature, COP reduces 3.5%, and for 10% increase in ambient relative humidity, COP increases about 6.5%. Also, by increasing the air volumetric flow rate of condenser about 10%, COP increases about 5%. Effect of increasing the condenser area on its heat rejection rate was studied and it was found that increasing the condenser area, increases the heat rejection rate substantially only in a limited range and after that it does not change.

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In this paper, the combined carbon dioxide power and ejector compression refrigeration cogeneration cycle with the ability to change the production capacity of power and cooling ​​by changing the performance parameters of the cogeneration cycle has been analyzed. Thermodynamic simulation of the studied cogeneration cycle has performed in EES software and the energy and exergy balance equations for each component of the cycle are applied. Then, a parametric study has been carried out and the variations of the performance parameters of the cogeneration cycle, including the turbine inlet temperature and pressure, the outlet pressure of the power cycle, the evaporator temperature, etc. are investigated on the overall thermodynamic performance of the cogeneration cycle. The results indicate that the exergy efficiency of the studied cogeneration cycle reaches to the optimum value of 28.8% at the turbine inlet pressure of 21100 kPa, while the maximum value of the total produced power and cooling of the studied cycle occurs at the turbine inlet pressure of 18600 kPa. Also the contribution of different components of the studied cogeneration cycle in the total exergy destruction rate is calculated and it is revealed that the turbine and the heater have the highest exergy destruction rate values, respectively, among the components of the cogeneration system