Numerical analysis of a resorption heat pump with two useful heating effects

This paper shows the advantages for using the ammonia-water solution in a resorption heat pump and the importance of optimizing both the coefficient of performance and the exergetic efficiency as a function of boiling pressure. The most important heating effect is realized through heat recovery from the absorber and the resorber in order to prepare hot water. A second heating effect is obtained through heat recovery from the vapor at the outlet of the vapor generator; this second effect is smaller in value, but the water temperature is higher. The system with two heating effects is characterized by higher values for the exergetic efficiency. This solution answers to some practical application where two temperature levels for the heat are required. The study was performed for different operating conditions of the plant.