Performance evaluation of a combined ejector-vapor compression cycle

This paper describes the development of a combined ejector-vapor compression cycle (EVCC) that uses working fluid R134a and air-cooled condensers for both sub-cycles. A large amount of experiments have been conducted to test the influence of the evaporating, generating and condensing temperatures of the ejector sub-cycle (ESC) on the performances of EVCC. The test results show that (1) the performance of the combined cycle is very sensitive to the three temperatures of ESC; (2) the variation of the degree of sub-cooling at the vapor compression sub-cycle (VCSC) is similar to that of COP improvement at EVCC over VCSC; and (3) this system with certain operating conditions results in relatively high COP improvements (15.9–21.0%).

► A combined ejector-vapor compression cycle (EVCC) was developed.
► The EVCC employed working fluid of R134a and air-cooled condensers.
►  The performance of the EVCC is very sensitive to three temperatures of the ESC.
► The EVCC achieved relatively high COP improvements (15.9–21.0%).