kr 1 Lecture Notes on Thermodynamics 2008 Chapter 8 Exergy Prof. Man Y. Kim, Autumn 2008, ⓒ Aerospace Engineering, Chonbuk National University, Korea

kr 2 Exergy : Work Potential Work= f ( initial state, path, final state) Exergy of Kinetic and Potential Energies To maximize the work, reversible process and final dead states are necessary dead state  Kinetic Energy :  Potential Energy :

kr 3 Reversible Work and Irreversibility Total Energy = Exergy + Unavailable Energy Surrounding Work : Useful Work : Reversible Work :  If the final state is dead state, reversible work becomes exergy Irreversibility : or  for energy production devices :  for energy consuming devices : Second Law Efficiency, for heat engine for refrigerator and heat pump

kr 4 Exergy Change Nonflowing (Closed System) Exergy Here, Flow Exergy

kr 5 Exergy Transfer by Heat, Work, and Mass Exergy Transfer by Heat Exergy Transfer by Work for boundary work for other forms of work Exergy Transfer by Mass

kr 6 Decrease of Exergy Principle Exergy Destruction Exergy Balance for a Closed System Exergy Balance for a Control Volume Reversible Work

kr 7 Homework #8 Solve the Problems 8–1C, 2C, 3C, 4C, 5C, 6C, 7C, 8C, 9C, 10C, 11C, 13C, 14C