Thermodynamics model and performance optimization of absorption heat pump

The absorption heat pump was studied with finite time thermodynamics. A four reservoirs model of absorption heat pump which is treated as an irreversible Carnot heat pump driven by an irreversible Carnot heat engine was established considering the heat resistance and the irreversibility of the internal cycle. The main performance limits and the approach of how to get it were deduced, and a generalized optimization relationship between the main parameters and the corresponding conditions were derived. It is show that, two internal irreversibility parameters, the heat engine cycle and the heat pump cycle has different effects on system performance, and the reduction of the friction, heat loss, and internal dissipations of the equivalent heat pump cycle are more important than its reduction of heat engine cycle. It is indicated that, the heating load of absorber and condenser should be the results by system optimization, and it is not correct to introduce a parameter as the heat allocation ratio of absorber and condenser, and also it is not correct to define the ratio as a definite valve.