Investigation of transfer coefficients for many-component dense systems of neutral and charged hard spheres

In present work a calculation of transfer coefficients for many-component dense gases for charged and non-charged hard spheres is carried out using the Enskog-Landau kinetic equation which takes into account realistic particle sizes.Comment: 4 pages, 2 eps-figure

Normal solution to the Enskog-Landau kinetic equation. Boundary conditions method

Nonstationary and nonequilibrium processes are considered on the basis of an Enskog-Landau kinetic equation using a boundary conditions method. A nonstationary solution of this equation is found in the pair collision approximation. This solution takes into account explicitly the influence of long-range interactions. New terms to the transport coefficients are identified. An application of the boundary conditions method to hydrodynamic description of fast processes is discussed.Comment: 11 LaTeX pages using Elsevier format elsart.st

Normal solution and transport coefficients to the Enskog-Landau kinetic equation for a two-component system of charged hard spheres. The Chapman-Enskog method

An Enskog-Landau kinetic equation for a many-component system of charged hard spheres is proposed. It has been obtained from the Liouville equation with modified boundary conditions by the method of nonequilibrium statistical operator. On the basis of this equation the normal solutions and transport coefficients such as bulk kappa and shear eta viscosities, thermal conductivity lambda, mutual diffusion D^{\alpha\beta} and thermal diffusion D_T^\alpha have been obtained for a binary mixture in the first approximation using the Chapman-Enskog method. Numerical calculations of all transport coefficients for mixtures Ar-Kr, Ar-Xe, Kr-Xe with different concentrations of compounds have been evaluated for the cases of absence and presence of long-range Coulomb interactions. The results are compared with those obtained from other theories and experiment.Comment: 24 LaTeX209 pages, 3 EPS figures (4 files). To be published in Physica

A consistent description of kinetics and hydrodynamics of systems of interacting particles by means of the nonequilibrium statistical operator method

A statistical approach to a self-consistent description of kinetic and hydrodynamic processes in systems of interacting particles is formulated on the basis of the nonequilibrium statistical operator method by D.N.Zubarev. It is shown how to obtain the kinetic equation of the revised Enskog theory for a hard sphere model, the kinetic equations for multistep potentials of interaction and the Enskog-Landau kinetic equation for a system of charged hard spheres. The BBGKY hierarchy is analyzed on the basis of modified group expansions. Generalized transport equations are obtained in view of a self-consistent description of kinetics and hydrodynamics. Time correlation functions, spectra of collective excitations and generalized transport coefficients are investigated in the case of weakly nonequilibrium systems of interacting particles.Представлено один із статистичних підходів узгодженого опису кінетичних та гідродинамічних процесів систем взаємодіючих частинок, що сформульований на основі методу нерівноважного статистичного оператора Д.М.Зубарєва. Показано, як із ланцюжка рівнянь ББГКІ з модифікованими граничними умовами отримуються кінетичне рівняння ревізованої теорії Енскога для моделі твердих сфер, кінетичне рівняння для багатосходинкового потенціалу та кінетичне рівняння Енскога-Ландау для моделі заряджених твердих сфер. Проаналізовано ланцюжки рівнянь ББГКІ на основі модифікованих групових розкладів. Отримано узагальнені рівняння переносу узгодженого опису кінетики та гідродинаміки. Для випадку слабо нерівноважних систем класичних взаємодіючих частинок при взаємному врахуванні кінетичних та гідродинамічних процесів досліджено часові кореляційні функції, спектр колективних збуджень та узагальнені коефіцієнти переносу

Thermo field hydrodynamic and kinetic equations of dense quantum nuclear systems

Basic equations of nonequilibrium thermo field dynamics of dense quantum systems are presented. A formulation of nonequilibrium thermo field dynamics has been performed using the nonequilibrium statistical operator method by D.N.Zubarev. Hydrodynamic equations have been obtained in thermo field representation. Two levels of the description of kinetics and hydrodynamics of a dense nuclear matter are considered. The first one is a quantum system with strongly coupled states, the second one is a quark-gluon plasma. Generalized transfer equations of a consistent description of kinetics and hydrodynamics have been obtained, as well as limiting cases are considered.Представлено основні рівняння нерівноважної термопольової динаміки густих квантових систем. Формулювання нерівноважної термопольової динаміки подано методом нерівноважного статистичного оператора Д.М.Зубарєва. Отримано рівняння гідродинаміки у термопольовому представленні. Розглянуто два рівні опису кінетики та гідродинаміки густої ядерної матерії: квантові системи сильно зв’язаних станів та кварк-глюонна плазма. Для цих систем отримано узагальнені рівняння переносу узгодженого опису кінетики та гідродинаміки. Розглянуто граничні випадки

Enskog-Landau kinetic equation. Calculation of the transport coefficients for charged hard spheres

Using charged hard spheres model as an example, the dense one-component plasma is considered. For this model the Enskog-Landau kinetic equation is obtained and its normal solution is found using the Chapman-Enskog method. Transport coefficients are obtained numerically and analytically and compared with the experimental data available.Comment: 13 LaTeX209 pages, 4 figures (emline-format for LaTeX

Pressure dependence of diffusion coefficient and orientational relaxation time for acetonitrile and methanol in water: DRISM/mode-coupling study

We present results of theoretical description and numerical calculation of the dynamics of molecular liquids based on the Reference Interaction Site Model / Mode-Coupling Theory. They include the temperature-pressure(density) dependence of the translational diffusion coefficients and orientational relaxation times for acetonitrile and methanol in water at infinite dilution. Anomalous behavior, i.e. the increase in mobility with density, is observed for the orientational relaxation time of methanol, while acetonitrile does not show any deviations from the usual. This effect is in qualitative agreement with the recent data of MD simulation and with experimental measurements, which tells us that presented theory is a good candidate to explain such kind of anomalies from the microscopical point of view and with the connection to the structure of the molecules.Comment: 10 pages, 2 eps-figures, 3 table

Quantum stochastic differential equations for boson and fermion systems -- Method of Non-Equilibrium Thermo Field Dynamics

A unified canonical operator formalism for quantum stochastic differential equations, including the quantum stochastic Liouville equation and the quantum Langevin equation both of the It\^o and the Stratonovich types, is presented within the framework of Non-Equilibrium Thermo Field Dynamics (NETFD). It is performed by introducing an appropriate martingale operator in the Schr\"odinger and the Heisenberg representations with fermionic and bosonic Brownian motions. In order to decide the double tilde conjugation rule and the thermal state conditions for fermions, a generalization of the system consisting of a vector field and Faddeev-Popov ghosts to dissipative open situations is carried out within NETFD.Comment: 69 page

Slip boundary conditions in nanofluidics from the molecular theory of solvation

We propose the derivation and calculation of the hydrodynamic slip length from the first principles of statistical mechanics, based on a combination of linear response theory and equilibrium molecular theory of solvation. The slip length obtained is independent of the type of flow and is related to the fluid organisation near the solid surface, as governed by the solid-liquid and liquid-liquid interactions. In a wide range of shear rates and surface-liquid interactions, the slip length is expressed in terms of the Green-Kubo-Nakano relations as a function of the anisotropic inhomogeneous time correlation function of density fluctuations of the liquid in contact with the surface. The presented treatment generalises the phenomenological definition of the friction coefficient and the slip length to a tensor quantity, which reflects an anisotropic nature of an ordered crystalline surface. We derive generic analytical expressions for the liquid-surface friction coefficient and slip length for an arbitrary surface-liquid interaction potential. We further illustrate it by numerical calculations for the case of a laminar flow of several molecular liquids and water, at ambient conditions in contact with the (100) FCC surface of gold, copper and nickel modelled using all-atom or united-atom models for liquids and the Steele potential for crystalline surfaces. The values obtained for slip length range from few to hundreds of nanometres and are consistent with experimental measurements. We also calculate pressure and temperature dependence on the slip length for water in a wide range of these thermodynamic parameters. The information obtained is intended to be used, in particular, to control or manipulate the flow in electrokinetic processes. \ua9 2011 Taylor & Francis.Peer reviewed: YesNRC publication: Ye

Enskog-Landau kinetic equation for multicomponent mixture. Analytical calculation of transport coefficients

The Enskog-Landau kinetic equation is considered to describe non-equilibrium processes of a mixture of charged hard spheres. This equation has been obtained in our previous papers by means of the non-equilibrium statistical operator method. The normal solution of this kinetic equation found in the first approximation using the standard Chapman-Enskog method is given. On the basis of the found solution the flows and transport coefficients have been calculated. All transport coefficients for multicomponent mixture of spherical Coulomb particles are presented analytically for the first time. Numerical calculations of thermal conductivity and thermal diffusion coefficient are performed for some specific mixtures of noble gases of high density. We compare the calculations with those ones for point-like neutral and charged particles