Thermodynamic analysis and optimization of a novel combined power and ejector refrigeration cycle – Desalination system

Abstract

A novel multi-generation hybrid system is proposed and analyzed in details from the viewpoint of thermodynamics. Using a zeotropic mixture as working fluid, the system consists of a power and ejector refrigeration cycle as well as a desalination system based on humidification and dehumidification processes. A parametric study is performed to specify the decision variables influencing the system performance prior to the optimization process. The optimization is conducted in two cases. In the first case, a single-objective optimization is carried out to maximize the overall exergy efficiency. In the second case, a multi-objective optimization is accomplished considering the net output power and refrigeration capacity as the objective functions.The results in the first case reveals a maximum overall exergy efficiency of 17.12% for which the net output power is 57.03 kW and the refrigeration capacity is 91.25 kW. In the case of multi-objective optimization, the results obtained from Pareto frontier shows a net produced power of 52.19 kW and a refrigeration capacity of 120.4 kW. With these data an overall exergy efficiency of 16.46% is calculated. The amount of fresh water calculated in case two is slightly higher than that obtained in case one.