Exact momentum and energy balances and entropy production in phenomenological irreversible thermodynamics of a continuous system

1969 ◽  
Vol 34 (9) ◽  
pp. 2483-2500 ◽  
Author(s):  
I. Samohýl
Keyword(s):  
Entropy Production ◽  
Continuous System ◽  
Irreversible Thermodynamics ◽  
Energy Balances

scholarly journals Irreversible thermodynamics of transport across interfaces

2011 ◽  
Vol 89 (10) ◽  
pp. 1041-1050 ◽  
Author(s):  
Matthew R. Sears ◽  
Wayne M. Saslow
Keyword(s):  
Entropy Production ◽  
Electric Current ◽  
Heating Rate ◽  
Chemical Potential ◽  
Magnetic Semiconductors ◽  
Spin Current ◽  
Irreversible Thermodynamics ◽  
Heat Current ◽  
Bulk Heating ◽  
Current Production

With spintronics applications in mind, we use irreversible thermodynamics to derive the rates of entropy production and heating near an interface when heat current, electric current, and spin current cross it. Associated with these currents are apparent discontinuities in temperature (ΔT), electrochemical potential (Δ[Formula: see text]), and spin-dependent “magnetoelectrochemical potential” (Δ[Formula: see text]). This work applies to magnetic semiconductors and insulators as well as metals, because of the inclusion of the chemical potential, μ, which is usually neglected in works on interfacial thermodynamic transport. We also discuss the (nonobvious) distinction between entropy production and heat production. Heat current and electric current are conserved, but spin current is not, so it necessitates a somewhat different treatment. At low temperatures or for large differences in material properties, the surface heating rate dominates the bulk heating rate near the surface. We also consider the case where bulk spin currents occur in equilibrium. Although a surface spin current (in A/m2) should yield about the same rate of heating as an equal surface electric current, production of such a spin current requires a relatively large “magnetization potential” difference across the interface.

scholarly journals Nonequilibrium Thermodynamics Based on the Distributions Containing Lifetime as a Thermodynamic Parameter

2011 ◽  
Vol 2011 ◽  
pp. 1-10 ◽  
Author(s):  
Vasiliy Vasiliy Ryazanov
Keyword(s):  
Stochastic Processes ◽  
Entropy Production ◽  
Thermodynamic Parameter ◽  
Nonequilibrium Thermodynamics ◽  
Irreversible Thermodynamics ◽  
Statistical Distributions ◽  
Extended Irreversible Thermodynamics ◽  
Nonequilibrium Entropy ◽  
Nonequilibrium States ◽  
Explicit Expressions

To describe the nonequilibrium states of a system, we introduce a new thermodynamic parameter—the lifetime of a system. The statistical distributions which can be obtained out of the mesoscopic description characterizing the behaviour of a system by specifying the stochastic processes are written down. The change in the lifetime values by interaction with environment is expressed in terms of fluxes and sources. The expressions for the nonequilibrium entropy, temperature, and entropy production are obtained, which at small values of fluxes coincide with those derived within the frame of extended irreversible thermodynamics. The explicit expressions for the lifetime of a system and its thermodynamic conjugate are obtained.

scholarly journals QUADRATIC REHEATING

1999 ◽  
Vol 08 (03) ◽  
pp. 307-323 ◽  
Author(s):  
LUIS P. CHIMENTO ◽  
ALEJANDRO S. JAKUBI
Keyword(s):  
Entropy Production ◽  
Linear Model ◽  
Particle Number ◽  
Equilibrium Mixture ◽  
Irreversible Thermodynamics ◽  
Decay Rates ◽  
Inflaton Field ◽  
Inflationary Scenario ◽  
Self Consistent ◽  
Reheating Process

The reheating process for the inflationary scenario is investigated phenomenologically. The decay of the oscillating massive inflaton field into light bosons is modeled after an out of equilibrium mixture of interacting fluids within the framework of irreversible thermodynamics. Self-consistent, analytic results for the evolution of the main macroscopic magnitudes like temperature and particle number densities are obtained. The models for linear and quadratic decay rates are investigated in the quasiperfect regime. The linear model is shown to reheat very slowly while the quadratic one is shown to yield explosive particle and entropy production. The maximum reheating temperature is reached much faster and its magnitude is comparable with the inflaton mass.

scholarly journals It is not the entropy you produce, rather, how you produce it

2010 ◽  
Vol 365 (1545) ◽  
pp. 1317-1322 ◽  
Author(s):  
Tyler Volk ◽  
Olivier Pauluis
Keyword(s):  
Entropy Production ◽  
Production Rate ◽  
Thought Experiment ◽  
Biological Evolution ◽  
Irreversible Thermodynamics ◽  
Entropy Production Rate ◽  
Chemical Systems ◽  
Principle Of Maximum Entropy ◽  
Relative Contribution ◽  
Principle Of Maximum

The principle of maximum entropy production (MEP) seeks to better understand a large variety of the Earth's environmental and ecological systems by postulating that processes far from thermodynamic equilibrium will ‘adapt to steady states at which they dissipate energy and produce entropy at the maximum possible rate’. Our aim in this ‘outside view’, invited by Axel Kleidon, is to focus on what we think is an outstanding challenge for MEP and for irreversible thermodynamics in general: making specific predictions about the relative contribution of individual processes to entropy production. Using studies that compared entropy production in the atmosphere of a dry versus humid Earth, we show that two systems might have the same entropy production rate but very different internal dynamics of dissipation. Using the results of several of the papers in this special issue and a thought experiment, we show that components of life-containing systems can evolve to either lower or raise the entropy production rate. Our analysis makes explicit fundamental questions for MEP that should be brought into focus: can MEP predict not just the overall state of entropy production of a system but also the details of the sub-systems of dissipaters within the system? Which fluxes of the system are those that are most likely to be maximized? How it is possible for MEP theory to be so domain-neutral that it can claim to apply equally to both purely physical–chemical systems and also systems governed by the ‘laws’ of biological evolution? We conclude that the principle of MEP needs to take on the issue of exactly how entropy is produced.

scholarly journals ENTROPY PRODUCTION OF ENTIRELY DIFFUSIONAL LAPLACIAN TRANSFER AND THE POSSIBLE ROLE OF FRAGMENTATION OF THE BOUNDARIES

Fractals ◽  
2015 ◽  
Vol 23 (03) ◽  
pp. 1550026 ◽  
Author(s):  
K. KARAMANOS ◽  
S. I. MISTAKIDIS ◽  
T. J. MASSART ◽  
I. S. MISTAKIDIS
Keyword(s):  
Entropy Production ◽  
Active Zone ◽  
Numerical Study ◽  
Near Field ◽  
Irreversible Thermodynamics ◽  
Koch Curve ◽  
Variational Functional ◽  
Numerical Resolution ◽  
New Interpretation

The entropy production and the variational functional of a Laplacian diffusional field around the first four fractal iterations of a linear self-similar tree (von Koch curve) is studied analytically and detailed predictions are stated. In a next stage, these predictions are confronted with results from numerical resolution of the Laplace equation by means of Finite Elements computations. After a brief review of the existing results, the range of distances near the geometric irregularity, the so-called "Near Field", a situation never studied in the past, is treated exhaustively. We notice here that in the Near Field, the usual notion of the active zone approximation introduced by Sapoval et al. [M. Filoche and B. Sapoval, Transfer across random versus deterministic fractal interfaces, Phys. Rev. Lett. 84(25) (2000) 5776;1 B. Sapoval, M. Filoche, K. Karamanos and R. Brizzi, Can one hear the shape of an electrode? I. Numerical study of the active zone in Laplacian transfer, Eur. Phys. J. B. Condens. Matter Complex Syst. 9(4) (1999) 739-753.]2 is strictly inapplicable. The basic new result is that the validity of the active-zone approximation based on irreversible thermodynamics is confirmed in this limit, and this implies a new interpretation of this notion for Laplacian diffusional fields.

Irreversible Thermodynamic Description of Domain Occurrences in Ferroics

2012 ◽  
Vol 560-561 ◽  
pp. 140-144
Author(s):  
Yuan Zhen Cai
Keyword(s):  
Phase Transitions ◽  
Entropy Production ◽  
Stationary State ◽  
Thermodynamic Description ◽  
Irreversible Thermodynamic ◽  
Irreversible Thermodynamics ◽  
Minimum Entropy ◽  
Spatial Symmetry ◽  
Domain Structures ◽  
Minimum Entropy Production

Based on the irreversible thermodynamics, a irreversible thermodynamic description of domain occurrences in ferroics such as ferroelectrics, ferromagnetics and ferroelastics was given. The ferroic domain structures occur at the ferroic phase transitions from the prototype phases to the ferroic phases. The processes of transition are stationary state processes so that the principle of minimum entropy production is satisfied. The domain occurrences are a consequence of this principle. The time-spatial symmetry related to the domains and their occurrences was also expounded.

Interdiffusion: Consistency of Darken's and Onsager's Methods

2015 ◽  
Vol 363 ◽  
pp. 29-34 ◽  
Author(s):  
J. Dąbrowa ◽  
Witold Kucza ◽  
Katarzyna Tkacz-Śmiech ◽  
Bogusław Bożek ◽  
Marek Danielewski
Keyword(s):  
Entropy Production ◽  
Explicit Form ◽  
Transport Coefficients ◽  
Irreversible Thermodynamics ◽  
Component System ◽  
Independent Components ◽  
Interdiffusion Process ◽  
Flux Formula ◽  
Phenomenological Coefficients ◽  
Interdiffusion Coefficients

The Nernst-Planck flux formula is used in Darken's method to obtain the interdiffusion fluxes. The effective interdiffusion potentials, derived for the independent components in the system, allow obtaining the symmetrical matrix of the interdiffusion coefficients. The transport coefficients for 2, 3 andr-component system are presented. Interpretation of obtained matrixes in the light of Onsager's theory of irreversible thermodynamics is shown. Equation for the entropy production in the interdiffusion process is displayed. The presented approach allows calculation of entropy production during interdiffusion, as well as formulating Onsager's phenomenological coefficients for the interdiffusion in an explicit form, a form which is directly correlated with the mobilities of the atoms present in the system.

Entropy Production and Stress–Deformation Effect on Interdiffusion

2012 ◽  
Vol 323-325 ◽  
pp. 43-48 ◽  
Author(s):  
Marek Danielewski
Keyword(s):  
Entropy Production ◽  
Production Rate ◽  
Reference Frame ◽  
Elastic Deformation ◽  
Irreversible Thermodynamics ◽  
Special Consideration ◽  
Deformation Effect ◽  
Entropy Balance ◽  
Ni Alloys ◽  
Linear Irreversible Thermodynamics

A general, consistent with linear irreversible thermodynamics, theory of stress and elastic deformation during interdiffusion is shown. Special consideration is given to the entropy balance and its production rate during diffusion in Cu-Fe-Ni alloys. The entropy produced during diffusion does not depend on the reference frame and is always positive. The paper spans the gap between the Darken method, linear irreversible thermodynamics and treatments by Stephenson and Svoboda.

Sign in / Sign up

Export Citation Format

Share Document