Advanced exergy analysis of a jet ejector refrigeration cycle used to cool down the intake air in an internal combustion engine

Abstract

[EN] This paper describes a jet ejection cycle coupled to a 1.5 L diesel engine to reduce the intake air temperature using the waste heat of the exhaust gases. This cycle is evaluated by means of conventional and advanced exergy analysis. The conventional analysis allows to determine the origin and magnitude of the irreversibilities, whereas the advanced analysis sheds light on the mutual interdependencies between components and the real improvement potential considering technological limitations. From the conventional exergy analysis it is inferred that more than a half of exergy destruction is due to generator followed by ejector (one third part) and condenser. However, the advanced exergy analysis suggests that the ejector plays a prominent role because the avoidable endogenous part corresponds to 42% of total exergy destruction in that component whereas the avoidable part of exergy destruction in the generator is mostly exogenous (83%). Hence, exergy destruction could be significantly reduced if improvement efforts are focused on the ejector instead of other components like the generator.