Internal variables in the local-equilibrium approximation

Conference · Fri May 01 00:00:00 EDT 1992

OSTI ID:7206169

Kestin, J

We explore the basis and consequences of the formalism known in the literature as the method of local equilibrium. Contemporary controversies regarding the foundations of thermodynamics are rooted not only in different sets of concepts and principles, but also in semantics. An attempt is made here to use a consistent group of terms, each of whose dictionary meaning corresponds to its physical nature as closely as possible. Since the intention is to study irreversible processes in systems in which even locally there prevails a state of nonequilibrium, the term local equilibrium is abandoned in favor of the phrase principle of local state. In defining the thermodynamic state of system, a distinction is made between the intensive parameters which appear in the physical space and those which describe states of constrained equilibrium in the Gibbsian phase space. The principle of local state is applied by association with every nonequilibrium state n and accompanying equilibrium state e of equal values of U, a, {alpha}, and by asserting that the entropy {bar S} assignable in physical space and temperature {bar T} measured in it can be approximated by the values S and T calculated in the Gibbsian phase space by standard, classical methods. A continuous sequence of accompanying equilibrium states is called an accompanying reversible process, it is conceived as an adiabatic projection of the continuous sequence of nonequilibrium states. The essential part of the method consists in the formulation of the Gibbs equation for the accompanying reversible process in the phase space. It is noted that the local-state approximation, made explicit in this paper, has been used and tested in fluid mechanics though its validity is contested in contemporary continuum mechanics and mechanics of solids.

• Research Organization: Brown Univ., Providence, RI (United States). Div. of Engineering
• Sponsoring Organization: USDOE; USDOE, Washington, DC (United States)
• DOE Contract Number: FG02-87ER13687
• OSTI ID: 7206169
• Report Number(s): DOE/ER/13687-10; CONF-9206208-1; ON: DE92016854
• Resource Relation: Conference: Symposium on thermodynamic fundamentals, Berlin (Germany), 11-12 Jun 1992
• Country of Publication: United States
• Language: English

Related Subjects

71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
IRREVERSIBLE PROCESSES
LTE
ANALYTICAL SOLUTION
THERMODYNAMICS
CLASSICAL MECHANICS
ENTROPY
EQUATIONS OF STATE
FLUID MECHANICS
FREE ENTHALPY
ENERGY
EQUATIONS
EQUILIBRIUM
MECHANICS
PHYSICAL PROPERTIES
THERMODYNAMIC PROPERTIES
661300* - Other Aspects of Physical Science- (1992-)