Recent Advancements in Numerical Investigations on Enhancement of Bi-evaporator Compression Refrigeration System Using Ejector as Expansion Device

Nowadays, many cold storage applications require varied types of cooling loads to be connected to same refrigeration system. This shall be accomplished by feeding refrigerant to multi-evaporators. A bi-evaporator single compression system with individual expansion valves or with multiple arrangement of expansion valves is commonly used to meet this requirement. With increasing demand for energy conservation, it is necessary to further improve the efficiency of these types of refrigeration systems. One such method is using a two-phase ejector as expansion device in place of expansion valve, to enhance the system performance. Performance of this ejector-bi-evaporator compression refrigeration system will be assessed by carrying out energy analysis by means of numerical simulation in MATLAB and comparing with that of conventional expansion valve-bi-evaporator compression refrigeration system. R134a will be used as working fluid and the effect of evaporator temperature and condenser temperature on cooling capacity and coefficient of performance will be studied. Generally, performance of bi-evaporator ejector expansion VCRS shows marked improvement compared to conventional bi-evaporator VCRS and offers a better cooling solution for efficient cold storage systems which require cooling loads to be maintained at different evaporator temperatures.