Recovery of Waste Heat from Refrigeration Machines

Conventional water heating and desalination methods are energy-intensive and costly. To remedy this problem, coupling a refrigeration machine with a domestic water heating unit and/or a brackish water distillation unit represents a promising and economical solution. The aim of this project is to carry out a theoretical and experimental study of two domestic refrigerators which, in addition to their main refrigeration function, also heat domestic hot water. The study also concerns an air conditioner which, in addition to its basic function, distills brackish or sea water. The theoretical study involves modeling the operation and coupling of the refrigerator to the water heater. The proposed mathematical model is validated by comparing theoretical results with experiments carried out at ENIG’s Energy, Water, Environment and Processes research laboratory, and also by comparing the model’s numerical results with existing work in the literature. A numerical study is carried out to optimize the geometry of the helical condenser dedicated to the water heating process.