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The absorption-compression heat pump (ACHP) has been considered as an effective approach to recover and utilize low-grade heat sources. In the present study, the first and second law thermodynamic analyses of the ACHP with NH3/H2O as working fluid were performed. Thermodynamic properties of each point and heat transfer rate of each component in the cycle under basic operation conditions were calculated from the first law analysis. Following the second law of thermodynamics, the entropy generation of each component and the total entropy generation of the system were obtained. The effects of the heating temperature, heat source temperature, and compression ratio on the coefficient of performance (COP) and the total entropy generation (STot) of the system were examined. The results show that the increase in COP corresponds to a decrease in STot, and vice versa; besides, for certain operating conditions, an optimum compression ratio in the NH3/H2O ACHP exists.
The absorption-compression heat pump (ACHP) has been considered as an effective approach to recover and utilize low-grade heat sources. In the present study, the first and second law thermodynamic analyzes of the ACHP with NH3 / H2O as working fluid were performed . Thermodynamic properties of each point and heat transfer rate of each component in the cycle under basic operating conditions were calculated from the first law analysis. The effects of the heating temperature, heat source temperature, and compression ratio on the coefficient of performance (COP) and the total entropy generation (STot) of the system were examined. The results show that the increase in COP corresponded to a decrease in STot, and vice versa; besides, for certain operating conditions, an optimum compression ratio in the NH3 / H2O ACHP exists.