Abstract
An extremal principle is formulated for thermodynamic systems near equilibrium subjected to various external conditions. It is shown that the principle describes unambiguously the kinetics of the thermodynamic system and replaces classical phenomenological equations. The global formulation of the principle makes it possible i) to introduce discrete characteristic parameters for the proper description of the state and evolution of the system, ii) to take into account constraints amongst the characteristic parameters of the local or global character and iii) to derive the evolution equations for the characteristic parameters. These facts turn the principle into an effective tool for the treatment of non-equilibrium thermodynamic systems.
Acknowledgements
The authors are indebted to Materials Center Leoben Forschung GmbH and the Austrian Kplus programme for financial support within the strategic project MCL SP16. The work on the project was also partly supported by the Academy of Sciences of the Czech Republic under the Grant 1QS200410502.