This paper is a followup of previous work aimed at the identification and quantification of the exergy of macroscopic nonequilibrium systems. Assuming that both energy and exergy are a priori concepts, it is possible to show that a system in an initial nonequilibrium state relaxes to equilibrium releasing (or absorbing) an additional amount of exergy, called nonequilibrium exergy, which is fundamentally different from Gibbs’ Available Energy and depends on both the initial state and the imposed boundary conditions. The existence of such a quantity implies that all isoenergetic nonequilibrium states can be ranked in terms of their nonequilibrium exergy content, any point of the Gibbs plane corresponding therefore to a possible initial distribution, each one with its own exergydecay history. The nonequilibrium exergy is always larger than its equilibrium counterpart and constitutes the “real” total exergy content of the system, i.e., the real maximum work extractable (or absorbable) from the system. The application of the method to heat conduction problems led to the calculation of a “relaxation curve”, i.e., to the determination of the timehistory of the relaxation towards equilibrium that takes place in finite rather than infinite time interval. In our previous works, use was made of the Fourier heat diffusion equation. In this study, the Cattaneo heat transfer equation is used instead, in an attempt to extend the validation range of the procedure. Cattaneo introduced in 1948 a second time derivative term that renders the diffusion equation hyperbolic and avoids an infinite speed of propagation. A finite propagation velocity of thermal disturbances affects the value of the nonequilibrium exergy: this paper presents the new results and offers a discussion of the implications.
nonequilibrium thermodynamics, Cattaneo equation, exergy, heat diffusion
Birincil Dil  İngilizce 

Konular  Mühendislik 
Bölüm  Regular Original Research Article 
Yazarlar 

Yayımlanma Tarihi  2 Mart 2019 
Yayınlandığı Sayı  Yıl 2019, Cilt 22, Sayı 1 
Bibtex  @araştırma makalesi { ijot515606, journal = {International Journal of Thermodynamics}, issn = {13019724}, eissn = {21461511}, address = {}, publisher = {Uluslararası Uygulamalı Termodinamik Derneği İktisadi İşletmesi}, year = {2019}, volume = {22}, number = {1}, pages = {19  24}, doi = {10.5541/ijot.515606}, title = {On the quantification of nonequilibrium exergy for thermodynamic systems evolving according to Cattaneo’s equation}, key = {cite}, author = {Zullo, Federico and Sciubba, Enrico} } 
APA  Zullo, F. & Sciubba, E. (2019). On the quantification of nonequilibrium exergy for thermodynamic systems evolving according to Cattaneo’s equation . International Journal of Thermodynamics , 22 (1) , 1924 . DOI: 10.5541/ijot.515606 
MLA  Zullo, F. , Sciubba, E. "On the quantification of nonequilibrium exergy for thermodynamic systems evolving according to Cattaneo’s equation" . International Journal of Thermodynamics 22 (2019 ): 1924 <https://dergipark.org.tr/tr/pub/ijot/issue/43635/515606> 
Chicago  Zullo, F. , Sciubba, E. "On the quantification of nonequilibrium exergy for thermodynamic systems evolving according to Cattaneo’s equation". International Journal of Thermodynamics 22 (2019 ): 1924 
RIS  TY  JOUR T1  On the quantification of nonequilibrium exergy for thermodynamic systems evolving according to Cattaneo’s equation AU  FedericoZullo, EnricoSciubba Y1  2019 PY  2019 N1  doi: 10.5541/ijot.515606 DO  10.5541/ijot.515606 T2  International Journal of Thermodynamics JF  Journal JO  JOR SP  19 EP  24 VL  22 IS  1 SN  1301972421461511 M3  doi: 10.5541/ijot.515606 UR  https://doi.org/10.5541/ijot.515606 Y2  2019 ER  
EndNote  %0 International Journal of Thermodynamics On the quantification of nonequilibrium exergy for thermodynamic systems evolving according to Cattaneo’s equation %A Federico Zullo , Enrico Sciubba %T On the quantification of nonequilibrium exergy for thermodynamic systems evolving according to Cattaneo’s equation %D 2019 %J International Journal of Thermodynamics %P 1301972421461511 %V 22 %N 1 %R doi: 10.5541/ijot.515606 %U 10.5541/ijot.515606 
ISNAD  Zullo, Federico , Sciubba, Enrico . "On the quantification of nonequilibrium exergy for thermodynamic systems evolving according to Cattaneo’s equation". International Journal of Thermodynamics 22 / 1 (Mart 2019): 1924 . https://doi.org/10.5541/ijot.515606 
AMA  Zullo F. , Sciubba E. On the quantification of nonequilibrium exergy for thermodynamic systems evolving according to Cattaneo’s equation. International Journal of Thermodynamics. 2019; 22(1): 1924. 
Vancouver  Zullo F. , Sciubba E. On the quantification of nonequilibrium exergy for thermodynamic systems evolving according to Cattaneo’s equation. International Journal of Thermodynamics. 2019; 22(1): 1924. 
IEEE  F. Zullo ve E. Sciubba , "On the quantification of nonequilibrium exergy for thermodynamic systems evolving according to Cattaneo’s equation", International Journal of Thermodynamics, c. 22, sayı. 1, ss. 1924, Mar. 2019, doi:10.5541/ijot.515606 