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Dissipative macroscopic systems nonequilibrium thermodynamics

Extended nonequilibrium thermodynamics is not based on the local equilibrium hypothesis, and uses the conserved variables and nonconserved dissipative fluxes as the independent variables to establish evolution equations for the dissipative fluxes satisfying the second law of thermodynamics. For conservation laws in hydrodynamic systems, the independent variables are the mass density, p, velocity, v, and specific internal energy, u, while the nonconserved variables are the heat flux, shear and bulk viscous pressure, diffusion flux, and electrical flux. For the generalized entropy with the properties of additivity and convex function considered, extended nonequilibrium thermodynamics formulations provide a more complete formulation of transport and rate processes beyond local equilibrium. The formulations can relate microscopic phenomena to a macroscopic thermodynamic interpretation by deriving the generalized transport laws expressed in terms of the generalized frequency and wave-vector-dependent transport coefficients. [Pg.681]

Now definitions or frameworks of modem thermodynamics in a broad sense, of classical thermodynamics, and of modem thermodynamics in a narrow sense are very clear. Modern thermodynamics in a broad sense includes all fields of thermodynamics (both classical thermodynamics and modem thermodynamics in a narrow sense) for any macroscopic system, but modem thermodynamics in a narrow sense includes only three fields of thermodynamics, i.e., nonequilibrium nondissipative thermodynamics, linear dissipative thermodynamics and nonlinear dissipative thermodynamics. The modem thermodynamics in a narrow sense should not be called nonequilibrium thermodynamics, because the classical nonequilibrium thermodynamics is not included. Meanwhile, the classical thermodynamics should only be applied to simpler systems without reaction coupling. That is, the application of classical thermodynamics to some modem inorganic syntheses and to the life science may be not suitable. Without the self-consistent classification of modem thermodynamics it was very difficult to really accept the term of modem thermodynamics even only for teaching courses. [Pg.546]

There are two types of macroscopic structures equilibrium and dissipative ones. A perfect crystal, for example, represents an equilibrium structure, which is stable and does not exchange matter and energy with the environment. On the other hand, dissipative structures maintain their state by exchanging energy and matter constantly with environment. This continuous interaction enables the system to establish an ordered structure with lower entropy than that of equilibrium structure. For some time, it is believed that thermodynamics precludes the appearance of dissipative structures, such as spontaneous rhythms. However, thermodynamics can describe the possible state of a structure through the study of instabilities in nonequilibrium stationary states. [Pg.634]


See other pages where Dissipative macroscopic systems nonequilibrium thermodynamics is mentioned: [Pg.10]    [Pg.98]    [Pg.181]    [Pg.121]    [Pg.7822]    [Pg.98]    [Pg.70]    [Pg.84]    [Pg.347]   


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