Splitting physical exergy: Theory and application

Highlights: • Approaches for splitting the physical exergy are discussed. • The contribution of Professor Szargut is highlighted. • Theoretical model is reviewed and adjusted. • Graphical model is developed. • Applications of the model are demonstrated. -- Abstract: Splitting the physical exergy of a material stream into its thermal and mechanical parts represented a new direction in the development of exergy analysis discussed in publications of Professor Jan Szargut (Silesian University of Technology, Gliwice, Poland) and his research group. This information is necessary for improving the accuracy of an exergy analysis. It was found later, that this splitting also facilitates the application of exergy-based methods to optimization. In this paper both theoretical and graphical models are developed for splitting the physical exergy. An engineering method is necessary for designing and evaluating energy systems as well as for teaching purposes. The application is demonstrated using a one-component working fluid, and mixtures, including humid air.