The behavior of an ejector cooling system operating with refrigerant blends 410A and 507

摘要

The effect of refrigerant blends 410A and 507 on the operation of an ejector cooling system -ECS- is theoretically studied with the aid of a validated multi-geometry ejector mathematical model. For a system cooling capacity of 1 kW, a set of possible design conditions were obtained by means of a parametric study varying the generator, condenser and evaporator temperatures from 50°C to 70°C; 30°C to 40°C and 5°C to 15°C. The ejector's lower U and Φ values are obtained when R410A is employed, meaning higher primary fluid mass flow rates and smaller ejectors, respectively. ECS's upper COP_s values are achieved at higher T_(GE) and T_(EV) with lower T_(CO). An ECS operating with these blends has a higher COP_s using R410A, around 0.53 for T_(GE), T_(CO) and T_(EV) of 70°C, 30°C and 10°C, respectively. The system using R507 has a similar but slightly lower performance. Therefore, the systems employing R410A and R507 are good options when a maximum generation temperature of 70°C is available from a thermal source, either solar or industrial. As well, an ECS working with R410A and R507 experiences higher pressures and has a robust construction.