Performance analysis and optimization of heat pump driven liquid desiccant hybrid air-conditioning systems.

Heat pump driven liquid desiccant (HPLD) hybrid air-conditioning systems have been broadly used in hot and humid areas. However, it is difficult to evaluate and improve their performance, since structures of the HPLD systems are complex. In this paper, a systematical way to evaluate and improve the HPLD system is introduced. A novel HPLD-SR system is firstly proposed, and three different structures are analyzed with the first and second laws of thermodynamics. A validated numerical model for system simulation is used, and a new exergy calculation formulation of LiCl solution is presented, in the form of separate Gibbs energy equations. The results show that for system with solution self-cycles, its ECOPsys and exergy efficiency are 38.5% and 38.7% higher than that of the basic system. However, the system with double-stage dehumidification process shows the best performance. Its ECOPsys and exergy efficiency have increased to 4.81 and 0.162, respectively.