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Title: Least-entropy generation: Variational principle of Onsager's type for transient hyperbolic heat and mass transfer

Journal Article · · Physical Review A. General Physics; (United States)
;  [1]
  1. Department of Chemistry, The University of Chicago, 5735 South Ellis Avenue, Chicago, Illinois 60637 (United States)

For coupled transfer of the energy and mass in a multicomponent system at mechanical equilibrium a simple thermodynamic theory is developed, and the damped wave equations of change are derived. We show that under nonstationary conditions, where relaxation of diffusive fluxes is essential, the evolution of the distributed coupled transfer of the energy and mass follows the path that minimizes the difference between the total entropy generated within the system and that exchanged by the system. The principle is also valid in the limit in which flux relaxation effects are negligible and the heat and mass transfer, whether steady or not, obeys Onsager's generalization of the Fourier and Fick laws. For coupled steady-state processes the principle goes into that of Onsager, yielding his phenomenological equations. In contrast to the local steady-state nature of Onsager's principle the new principle is global, valid for both stationary and transient situations, and requires no frozen fields. For an isolated, distributed system, in which transient relaxation to equilibrium is the only possible process, the principle implies the least possible increase of the system entropy between any two successive configurations.

DOE Contract Number:
FG02-86ER13488
OSTI ID:
6950845
Journal Information:
Physical Review A. General Physics; (United States), Vol. 46:10; ISSN 1050-2947
Country of Publication:
United States
Language:
English