A Work Potential Perspective of Engine Component Performance

Abstract

There is a strong interest within the propulsion community in applying the concept of thermodynamic work potential as a universal figure of merit for gauging the performance of prime-movers. In particular, exergy, gas horsepower, and thrust work potential have shown considerable promise as work potential figures of merit for propulsion system design. However, the relationships between these measures of work potential and the classical measures of component performance (component efficiencies) are not widely known. The objective of this paper is to derive a series of relationships linking classical efficiency-based performance metrics to modern measures of work potential. Derivations for the most common component efficiencies encountered in aircraft engine design are given in terms of all three work potential measures previously mentioned. Finally, the classical efficiency-based models are compared and contrasted with modern work potential methods to highlight the strengths and weaknesses of each.