Allocation I 
Allocation II 
Cool / Heat 




What is Exergy?

DownLoad/Comprehension of Exergy on the T-s Chart of Steam.pdf

DownLoad/Comprehension of Exergy and Exergy Ratio on the T-s Chart of Air



Exergy is the amount of maximum work obtainable when some matter is brought to a state of thermodynamic equilibrium with ambient. The exergy is availability or useful work induced from carnot cycle, and this can calculate the irreversible loss work that occurs within any thermal or power cycle. The exergy ratio is the value of exergy divided by enthalpy of ambient reference, where the quality of energy or enthalpy in substances is evaluated by exergy ratio. Exergy is important in optimal design method of thermal system or each component, and the value of exergy at given state is calculated by the equation. Here, a designer can easily understand and find the value of enthalpy, because enthalpy is graphically drawn in chart, however exergy is not easily understood. In this paper, the exergy and exergy ratio of air, water, and steam were drawn on temperature-entropy chart. We wish to this chart is a help to the design, analysis, and education.

Keywords:  Air, Water, Steam, Exergy, Exergy ratio, Lost work, Reversible work

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