STUDY OF A SOLAR BOOSTER ASSISTED EJECTOR REFRIGERATION SYSTEM WITH R134a

摘要

A parametric study for a booster assisted ejector refrigeration system in steady state is carried out employing Lu's ejector model in transition regime. The range of generator and condenser temperatures is considered for a solar powered system. Conceiving the ejector geometry, through the area ratio φ and the main throat area A~*, and the system behavior, through the energy efficiency COP_s, the exergy efficiency ε_s and energy ratio Er, it was found that their extreme values, lowest for A~* and highest for the remainder, are reached at the highest generator temperature, T_(GE), and booster discharge pressure, p_(DIS), with the lowest condenser temperature, T_(CO), for the considered evaporator temperature, T_(EV), of -10℃. In regard to the ejector behavior, its maximum efficiency value, η_(EJ), is reached for the highest T_(GE) and the lowest T_(CO) for an intermediate p_(DIS). If T_(CO) is increased, the maximum η_(EJ) value is achieved at a higher p_(DIS). In spite of that the maximum η_(EJ) value is not reached at the highest p_(DIS), its influence is not reflected in system behavior because U always increases and its maximum value agrees with theory. The most important system and ejector parameters are presented as a reference.