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The expression for the entropy flux is analysed from the point of view of irreversible thermodynamics. In connection with this problem the evolution equations for the heat flux and for the electric current density including nonlocal terms are derived and discussed. The relation for the entropy flux is compared with that obtained by the statistical nonequilibrium thermodynamics on the basis founded on a generalized Gibbs' ensemble method for nonequilibrium systems.  相似文献   

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T. D. Frank   《Physica A》2002,310(3-4):397-412
Recently, Compte and Jou derived nonlinear diffusion equations by applying the principles of linear nonequilibrium thermodynamics to the generalized nonextensive entropy proposed by Tsallis. In line with this study, stochastic processes in isolated and closed systems characterized by arbitrary generalized entropies are considered and evolution equations for the process probability densities are derived. It is shown that linear nonequilibrium thermodynamics based on generalized entropies naturally leads to generalized Fokker–Planck equations.  相似文献   

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This paper studies a mathematical formalism of nonequilibrium thermodynamics for chemical reaction models with N species, M reactions, and general rate law. We establish a mathematical basis for J. W. Gibbs’ macroscopic chemical thermodynamics under G. N. Lewis’ kinetic law of entire equilibrium (detailed balance in nonlinear chemical kinetics). In doing so, the equilibrium thermodynamics is then naturally generalized to nonequilibrium settings without detailed balance. The kinetic models are represented by a Markovian jumping process. A generalized macroscopic chemical free energy function and its associated balance equation with nonnegative source and sink are the major discoveries. The proof is based on the large deviation principle of this type of Markov processes. A general fluctuation dissipation theorem for stochastic reaction kinetics is also proved. The mathematical theory illustrates how a novel macroscopic dynamic law can emerges from the mesoscopic kinetics in a multi-scale system.  相似文献   

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It is shown that the distribution function and the statistical operator, in the case that the considered system is close to the equilibrium state, can be received by the method relying upon minimizing the information gain, which is connected with the transition of the system from a nonequilibrium state to the equilibrium state. For the systems far from equilibrium the nonequilibrium distribution function or the nonequilibrium statistical operator can be derived using a variational principle based on Jaynes' maximum entropy formalism including memory effects.  相似文献   

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The Gibbsian relation is of fundamental importance to the thermodynamics of nonequilibrium systems. In this paper, we shall present an analytical derivation and several generalizations of this relation for dilute, nonequilibrium and certain highly nonequilibrium, systems. Our analysis will beindependent of the collision dynamics, because it will be based on the general kinetic equation witharbitrary collision integrals. Consequently, our analysis can provide athermodynamic derivation and several generalizations of the Gibbsian relation. Our distribution functions can also admit some arbitrary, nonequilibrium and highly nonequilibrium, forms. With the help of the generalized Gibbsian relation and a fundamental axiom to be postulated, the entropy production rates and the generalized forces and fluxes will be studied for our highly nonequilibrium systems. The second law of thermodynamics will be postulated and verified in specific cases. Onsager's reciprocity relations will be discussed.  相似文献   

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An information gain depending on two nonequilibrium coarse-grained statistical operators is discussed. The relation between the time derivative of information gain and excess entropy production is derived. Prigogine's stability criterion is expressed by means of the information gain. It is shown in the domain of linear nonequilibrium thermodynamics that zero time derivative of information gain corresponds to a minimum of entropy production and K theorem can be formulated.  相似文献   

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The problem of the kinetic justification of the generalized thermodynamics of nonequilibrium processes using the method of moments for solving the kinetic equation for a multicomponent gas mixture is examined. Generalized expressions are obtained for the entropy density, entropy flux density, and entropy production as functions of an arbitrary number of state variables (moments of the distribution function). Different variants of writing the relations between fluxes and thermodynamic forces are considered, which correspond to the Onsager version for spatially homogeneous systems and, in a more general case, lead to the generalized thermodynamic forces of a complicated form, including derivatives of the fluxes with respect to time and spatial coordinates. Some consequences and new physical effects, following from the obtained equations, are analyzed. It is shown that a transition from results of the method of moments to expressions for the entropy production and the corresponding phenomenological relations of the generalized nonequilibrium thermodynamics is possible on the level of a linearized Barnett approximation of the Chapman–Enskog method.  相似文献   

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Fluctuation theorems have been applied successfully to any system away from thermal equilibrium, which are helpful for understanding the thermodynamic state evolution. We investigate fluctuation theorems for strong coupling between a system and its reservoir, by path-dependent definition of work and heat satisfying the first law of thermodynamics. We present the fluctuation theorems for two kinds of entropy productions. One is the informational entropy production, which is always non-negative and can be employed in either strong or weak coupling systems. The other is the thermodynamic entropy production, which differs from the informational entropy production at strong coupling by the effects regarding the reservoir. We find that, it is the negative work on the reservoir, rather than the nonequilibrium of the thermal reservoir,which invalidates the thermodynamic entropy production at strong coupling. Our results indicate that the effects from the reservoir are essential to understanding thermodynamic processes at strong coupling.  相似文献   

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The tendency of the entropy to a maximum as an isolated system is relaxed to the equilibrium (the second law of thermodynamics) has been known since the mid-19th century. However, independent theoretical and applied studies, which suggested the maximization of the entropy production during nonequilibrium processes (the so-called maximum entropy production principle, MEPP), appeared in the 20th century. Publications on this topic were fragmented and different research teams, which were concerned with this principle, were unaware of studies performed by other scientists. As a result, the recognition and the use of MEPP by a wider circle of researchers were considerably delayed. The objectives of the present review consist in summation and analysis of studies dealing with MEPP. The first part of the review is concerned with the thermodynamic and statistical basis of the principle (including the relationship of MEPP with the second law of thermodynamics and Prigogine's principle). Various existing applications of the principle to analysis of nonequilibrium systems will be discussed in the second part.  相似文献   

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Summary Using a nonlinear transport theory, derived from the nonequilibrium statistical operator method, we obtain the equations that govern the evolution of the nonequilibrium state of a highly photoexcited direct-gap polar semiconductor, and its nonequilibrium mobility coefficient. It provides an analytic method that allows for a deep physical insight into the influence of the nonequilibrium irreversible evolution of the plasma in the semiconductor on its transport properties. We demonstrate that, under quite general conditions, the strong dependence of the momentum and energy relaxation times on the irreversible evolution of the macroscopic nonequilibrium state of the system results in the existence of a structured transient mobility,i.e. one with maxima and minima, with or without overshoot. A criterion for the occurrence of this structure is derived as well as several general properties of the ultrafast transient are discussed. The authors of this paper have agreed to not receive the proofs for correction.  相似文献   

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General kinetic equation for statistical systems is presented. A kinetic equation with source that is fluctuation of physical values was obtained. A new statistical criterion of systems evolution was determined. Nonequilibrium statistical and variational derivations of general kinetic equations are considered. Evolution of nonequilibrium Boltzmann-Gibbs-Shannon entropy, Hamilton function and Hamilton function production are examined.  相似文献   

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The challenge of calculating nonequilibrium entropy in polymeric liquids undergoing flow was addressed from the perspective of extending equilibrium thermodynamics to include internal variables that quantify the internal microstructure of chain-like macromolecules and then applying these principles to nonequilibrium conditions under the presumption of an evolution of quasie equilibrium states in which the requisite internal variables relax on different time scales. The nonequilibrium entropy can be determined at various levels of coarse-graining of the polymer chains by statistical expressions involving nonequilibrium distribution functions that depend on the type of flow and the flow strength. Using nonequilibrium molecular dynamics simulations of a linear, monodisperse, entangled C1000H2002 polyethylene melt, nonequilibrium entropy was calculated directly from the nonequilibrium distribution functions, as well as from their second moments, and also using the radial distribution function at various levels of coarse-graining of the constituent macromolecular chains. Surprisingly, all these different methods of calculating the nonequilibrium entropy provide consistent values under both planar Couette and planar elongational flows. Combining the nonequilibrium entropy with the internal energy allows determination of the Helmholtz free energy, which is used as a generating function of flow dynamics in nonequilibrium thermodynamic theory.  相似文献   

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We show that starting with either the non-extensive Tsallis entropy in Wang's formalism or the extensive Rényi entropy, it is possible to construct equilibrium non-Gibbs canonical distribution functions which satisfy the fundamental equations of thermodynamics. The statistical mechanics with Tsallis entropy does not satisfy the zeroth law of thermodynamics at dynamical and statistical independence request, whereas the extensive Rényi statistics fulfills all requirements of equilibrium thermodynamics in the microcanonical ensemble. Transformation formulas between Tsallis statistics in Wang representation and Rényi statistics are presented. The one-particle distribution function in Rényi statistics for a classical ideal gas at finite particle number has a power-law tail for large momenta.  相似文献   

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In this paper we investigate quantum statistical entropy for the Kehagias-Sfetsos black hole in IR modified Hořava-Lifshitz gravity by using t’ Hooft’s brick-wall method and generalized uncertainty principle method. By carefully calculating, we obtain the brick-wall entropy S BWM =A/4 and the generalized uncertainty principle entropy S GUP =A/96πγ. It is found if we view from quantum statistics, the brick-wall entropy and generalized uncertainty principle entropy may possibly is proportional to the event horizon area. This type area entropy is also justified by Wang et al. (Phys. Rev. D 81:083006, 2010). The study of the quantum statistical entropy may shed light on the understand of Hořava-Lifshitz gravity.  相似文献   

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For a quantum system weakly coupled to heat reservoirs, a statistical mechanical theory is developed in a formalism that dovetails perfectly with phenomenological thermodynamics. The present model is a modification of the many-reservoir model by Bergmann and Lebowitz. The method to be used here is based on the explicit introduction of external forces which bring about a deviation from equilibrium. These forces are assumed to arise from mechanical interaction with its surrounding which can be characterized thermodynamically. By an appropriate choice of reservoirs the Liouville-von Neumann equation is found to describe a heat conducting system. The nonequilibrium density matrices which describe such a system are found explicitly for some interesting cases. With these density matrices we obtain an expression for entropy production.  相似文献   

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胡隐樵 《物理学报》2003,52(6):1354-1359
利用大气非线性动力学证明了广义能量极小值原理,进一步从理论上证明它是同大气非平衡 态热力学最小熵产生原理在物理上是一致的.前者表明,强迫耗散动力系统的终态广义能量 达极小值;而最小熵产生原理表明,远离热力学平衡态的开放系其终态时系统内部的不可逆 过程最弱.而且,系统广义能量达极小值和系统熵产生达极小值的终态一般是一个稳定的定 态,它对应着系统的某种有序结构.也就是说它是一个“低耗高效”的有序定态.大气系统作 为自然界一个典型的物理复杂系统,其最小熵产生原理和广义能量极小值原理隐示了自然界 复杂系统的一个一 关键词: 强迫耗散系统 能量极值原理 有序结构 动力系统  相似文献   

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