English
Related papers

Related papers: The gas equation for stream

200 papers

Dust-gas mixtures are the simplest example of a two fluid mixture. We show that when simulating such mixtures with particles or with particles coupled to grids a problem arises due to the need to resolve a very small length scale when the…

Instrumentation and Methods for Astrophysics · Physics 2015-01-09 Daniel Price , Guillaume Laibe

We report on generic relations between fractional flow and pressure in steady two-phase flow in porous media. The main result is a differential equation for fractional flow as a function of phase saturation. We infer this result from two…

Condensed Matter · Physics 2007-05-23 Henning Arendt Knudsen , Alex Hansen

We study liquid-gas transitions of heat conduction systems in contact with two heat baths under constant pressure in the linear response regime. On the basis of local equilibrium thermodynamics, we propose an equality with a global…

Statistical Mechanics · Physics 2018-01-03 Naoko Nakagawa , Shin-ichi Sasa

We study the effect of transport processes (diffusion and free--streaming) on a collapsing spherically symmetric distribution of matter in a self--similar space--time. A very simple solution shows interesting features when it is matched…

General Relativity and Quantum Cosmology · Physics 2009-11-11 W. Barreto , C. Peralta , L. Rosales

We consider a non-interacting one-dimensional gas accelerated by a constant and uniform external field. The energy absorbed from the field is transferred via elastic collisions to a bath of scattering obstacles. At gas-obstacle encounters…

Statistical Mechanics · Physics 2009-11-11 Jaroslaw Piasecki , Rodrigo Soto

We investigate numerically the interaction of a stream of granular particles with a resting obstacle in two dimensions. For the case of high stream velocity we find that the force acting on the obstacle is proportional to the square of the…

Statistical Mechanics · Physics 2007-05-23 Volkhard Buchholtz , Thorsten Poeschel

An equation of state for the domain extending from hot gases to cool-dense fluids is formulated for a hydrogen-helium mixture. The physical processes take account of temperature ionization and dissociation, electron degeneracy, Coulomb…

Astrophysics · Physics 2009-10-30 G. Q. Luo

There is a long-standing question as to whether and to what extent it is possible to describe nonequilibrium systems in stationary states in terms of global thermodynamic functions. The positive answers have been obtained only for…

Statistical Mechanics · Physics 2022-11-30 Robert Hołyst , Karol Makuch , Anna Maciołek , Paweł J. Żuk

A brief derivation of a specific regularization for the magnetic gas dynamic system of equations is given in the case of general equations of gas state (in presence of a body force and a heat source). The entropy balance equation in two…

Analysis of PDEs · Mathematics 2025-12-30 Bernard Ducomet , Alexander Zlotnik

This work presents a comparative study of the best models available to describe granular fluids in order to investigate the extent to which it makes sense to speak about a liquid-gas transition in a system of particles that present no…

Soft Condensed Matter · Physics 2024-09-02 O. Coquand

For flows of a lossless gas, the stagnation enthalpy obeys a linear convected wave equation with coefficients which depend on the flow variables. This equation is self-adjoint and one has a reciprocity relation between source and observer.…

Fluid Dynamics · Physics 2010-09-21 Willi Mohring

There is a long-standing question of whether it is possible to extend the formalism of equilibrium thermodynamics to the case of non-equilibrium systems in steady states. We have made such an extension for an ideal gas in a heat flow…

Statistical Mechanics · Physics 2023-01-31 Robert Hołyst , Karol Makuch , Konrad Giżyński , Anna Maciołek , Paweł J. Żuk

A steady state of a granular gas with homogeneous granular temperature, no mass flow, and nonzero heat flux is studied. The state is created by applying an external position--dependent force or by enclosing the grains inside a curved…

Statistical Mechanics · Physics 2016-10-31 Nagi Khalil

We have considered a model of a small finite system with internal particles and surface degrees of freedom. All the main statistical distributions were explicitly obtained, on a pre thermodynamic limit basis. The concept of temperature or…

Statistical Mechanics · Physics 2025-08-11 D. M. Naplekov , V. V. Yanovsky

A picture for thermodynamics of the glassy state is introduced. It assumes that one extra parameter, the effective temperature, is needed to describe the glassy state. This explains the classical paradoxes concerning the Ehrenfest relations…

Disordered Systems and Neural Networks · Physics 2009-10-31 Th. M. Nieuwenhuizen

The equations of state for an ideal generalized gas, like an ideal quantum gas, are expressed in terms of power laws of the temperature. The reduction of an ideal generalized gas to an ideal classical case occurs when the characteristic…

Statistical Mechanics · Physics 2015-06-25 B. H. Lavenda

The flow of a gas through porous medium is considered in the case of pressure dependent permeability. Approximate self-similar solutions of the boundary-value problems are found.

Fluid Dynamics · Physics 2014-09-30 Nikolay A. Kudryashov , Mark B. Kochanov , Viktoria L. Savatorova

Thermodynamic properties of matter are conveniently expressed as functional relations between variables known as equations of state. Here we experimentally determine the compressibility, density and pressure equations of state for an…

Quantum Gases · Physics 2016-02-12 K. Fenech , P. Dyke , T. Peppler , M. G. Lingham , S. Hoinka , H. Hu , C. J. Vale

The departure from ideal gas behavior is described by several known equations of state (EoS), developed from a combination of theoretical considerations and experimental correlations. In this work a different approach is proposed, in which…

Statistical Mechanics · Physics 2011-03-31 D. Giusti , V. Molinari , D. Mostacci

We prove an existence result for the steady state flow of gas mixtures on networks. The basis of the model are the physical principles of the isothermal Euler equation, coupling conditions for the flow and pressure, and the mixing of…

Analysis of PDEs · Mathematics 2024-11-07 Alena Ulke , Michael Schuster , Simone Göttlich