What Does Extensity Mean in Endoreversible Thermodynamics?

[babbagee]

I am doing a project for my thermodynamics class and I have decided to do it on Endoreversible Thermodynamics. I Have read a few articles but I am having some difficulty understanding parts of it. I have not read the whole article, still in the beginning. But from the intro are they saying that Endoreversible engines overall are irreversible but can be broken down to multiple subsystems, which are reversible? Secondly I am having a hard time understanding what they mean by the use of the word extensity or extensities . Any help would be greatly Appreciated.

sorry totally forgot to link the article.

http://www.qucosa.de/fileadmin/data/qucosa/documents/5641/data/Masterarbeit.pdf

Thank you in advance

 

[Andy Resnick]

I quickly scanned the first 2 sections, 'extensity' seems to mean 'extensive variable', and 'intensity' means 'intensive variable'. For example, the entropy is extensvie (since doubling the size of the system doubles the entropy), but temperature is intensive- it remains the same.

The concept of endoreversible seems to be that irreversible systems can be approximated by directed fluxes of energy between reversible systems- the transport equations contain all the 'irreversible parts' of the system.