The purpose of this study is to examine the performance and the limits of the ejector refrigeration system using three new transitional refrigerants in hot climate in south of Algeria where the outside temperature reach, the variation of the coefficient of performance according to the heat sources is investigated, the parameters considered are the COP (Coefficient Of Performance), the ejector outlet pressure, and the maximum condensing temperature. The aim part of this research is to consider the performance of an ejector cooling system under climatic conditions of hot climate in south of Algeria where the temperature reach the fifty degrees in summer period. A study on the influence of the three source temperatures on the efficiency of the ejector cycle.

The system is evaluated for evaporator temperatures from 0°C to 20°C and condenser temperatures from 30 to 50 degrees Celsius.                                                    The system is optimized for each condition by selecting the optimal ejector parameters and generator temperature. R134a, R142b and R245fa are the three refrigerants used to optimizing the ejector. In all work situations, the refrigerant R245fa gives the best values of performance, more specifically, if the system provides cold at 20°C and removes heat at 30°C, the very extreme COP is 0.24. The code is written in Fortran programming code. This study consists of a study on a cooling system with ejector, the study starts by setting up a program for sizing the ejector according to characteristics of the three heat sources (evaporator, condenser and boiler), these results are validated by the experiment result within the VERPUR project (between CanmetNERGIE and Hydro-Qubec), then development of a simulation mode code to know the limitations of this ejector refrigeration cycle and the thermophysical properties of each point in the ejector for a given geometry. The findings of this research will provide valuable insights into the feasibility and efficiency of using transitional refrigerants in ejector cooling systems in a specific location like Constantine. This knowledge can contribute to developing sustainable and energy-efficient cooling solutions for various applications in the region and beyond.