Evaluating solar-driven ejector efficiency used in hybrid conventional air conditioning systems: a parametric study

In this paper, we investigated the performance of a hybrid ejector cooling system combined with a vapor system. The ejector system was operated at 70% and 80% of the compression cycle in the simulation. The hybrid ejector air conditioning system was modeled with EES software, and the refrigerant used was R134a. For maximum ejector performance, superheated conditions were assumed for the primary flow stream. The solar generator temperature ranged from 80 °C to 100 °C. The condenser temperature was from 30 °C to 40 °C, and the operating temperature of the evaporator was 8 °C to 12 °C. The obtained results indicated that under any operating condition, the optimum values of pressure drop in the suction chamber, ejector area ratio, ejector outlet pressure, and cooling coefficient of performance (COP) differed. The COP of the basic ejector cycle reached 0.616, given that the ejector cooling cycle worked in different conditions. By comparison, the value for the hybrid combined with the compression cycle system reached 0.91, which increased from 25% to 29% compared with the basic ejector cycle. The performance of the system with the ejector was better than that of the basic system even in the case of off design operation.