A dynamic model for study and optimization of an irreversible solar refrigerator

A general dynamic model for the study and optimization of reversed cycle thermal machines with three heat reservoirs is presented. The model is based on the First and Second Laws of Thermodynamics, heat transfer equations at finite thermal source and sink capacities, and entropy generation terms in order to consider the internal and external irreversibilities of the cycle. The proposed model is applied to an irreversible absorption machines for which several constraints are imposed. Some results generated by the model when applied to refrigeration machines are presented. They point out interesting results regarding the limits of the variation range for the model variables under different operating conditions and also for different variation laws for the internal entropy generation term. As a result, the model is expected to be a useful tool for simulation, design, and optimization of solar collector based energy systems.