English
Related papers

Related papers: Polytropic gas modelling at kinetic and macroscopi…

200 papers

A kinetic equation for a dilute gas of hard spheres confined between two parallel plates separated a distance smaller than two particle dimeters is derived. It is a Boltzmann-like equation, which incorporates the effect of the confinement…

Statistical Mechanics · Physics 2016-11-23 J. Javier Brey , P. Maynar , M. I. García de Soria

In this article we deduce a mathematical model of Maxwell-Stefan type for a reactive mixture of polyatomic gases with a continuous structure of internal energy. The equations of the model are derived in the diffusive limit of a kinetic…

Analysis of PDEs · Mathematics 2019-11-18 Benjamin Anwasia , Marzia Bisi , Francesco Salvarani , Ana Jacinta Soares

A kinetic model is proposed for rarefied flows of molecular gas with rotational and temperature-dependent vibrational degrees of freedom. The model reduces to the Boltzmann equation for monatomic gas when the energy exchange between the…

Fluid Dynamics · Physics 2022-01-19 Qi Li , Lei Wu

We propose a general multi-species Fokker-Planck model. We prove consistency of our model: conservation properties, positivity of all temperatures, H-Theorem and the shape of equilibrium as Maxwell distributions with the same mean velocity…

Analysis of PDEs · Mathematics 2024-09-25 Marlies Pirner

The length-scale dependence of the dynamic entropy is studied in a molecular dynamics simulation of a binary Lennard-Jones liquid above the mode-coupling critical temperature $T_c$. A number of methods exist for estimating the entropy of…

Soft Condensed Matter · Physics 2009-10-31 Paolo Allegrini , Jack F. Douglas , Sharon C. Glotzer

A dilute gas of hard disks confined between two straight parallel lines is considered. The distance between the two boundaries is in between one and two particle diameters, so that the system is quasi-one-dimensional. A Boltzmann-like…

Statistical Mechanics · Physics 2022-04-13 M. Mayo , J. Javier Brey , M. I. García de Soria , P. Maynar

We introduce a closure model for coarse-grained kinetic theories of polar active fluids. Based on a quasi-equilibrium approximation of the particle distribution function, the model closely captures important analytical properties of the…

Soft Condensed Matter · Physics 2022-06-17 Scott Weady , David B. Stein , Michael J. Shelley

We consider the socalled Bathnagar-Gross-Krook (BGK) model, an approximation of the Boltzmann equation, describing the time evolution of a single momoatomic rarefied gas and satisfying the same two main properties (conservation properties…

Analysis of PDEs · Mathematics 2021-10-26 Marlies Pirner

The most rigorous physical description of non-equilibrium gas dynamics is rooted in the numerical solution of the Boltzmann equation. Yet, the large number of degrees of freedom and the wide range of both spatial and temporal scales render…

Computational Physics · Physics 2024-10-25 Anthony Chang , Narendra Singh , Marco Panesi

A thermodynamically consistent particle-based model for fluid dynamics with continuous velocities and a non-ideal equation of state is presented. Excluded volume interactions are modeled by means of biased stochastic multiparticle…

Soft Condensed Matter · Physics 2009-11-11 Thomas Ihle , Erkan Tuzel , Daniel M. Kroll

We present the speedup from a novel parallel implementation of the multicanonical method on the example of a lattice gas in two and three dimensions. In this approach, all cores perform independent equilibrium runs with identical weights,…

Statistical Mechanics · Physics 2015-01-27 Johannes Zierenberg , Micha Wiedenmann , Wolfhard Janke

We present a comprehensive study of the discretized modes of an atomic gas in different conditions of confinement. Starting from the equations of hydrodynamics we derive a closed equation for the velocity field, depending on the adiabatic…

Quantum Gases · Physics 2015-11-19 Giulia De Rosi , Sandro Stringari

Extended Thermodynamics is the natural framework in which to study the physics of fluids, because it leads to symmetric hyperbolic systems of field laws, thus assuming important properties such as finite propagation speeds of shock waves…

Mathematical Physics · Physics 2007-05-23 Sebastiano Pennisi , Maria Cristina Carrisi

In the present manuscript we consider the Boltzmann equation that models a polyatomic gas by introducing one additional continuous variable, referred to as microscopic internal energy. We establish existence and uniqueness theory in the…

Mathematical Physics · Physics 2020-08-19 Irene M. Gamba , Milana Pavić-Čolić

We propose a new model for the description of a gravitating multi particle system, viewed as a kinetic gas. The properties of the, colliding or non-colliding, particles are encoded into a so called one-particle distribution function, which…

General Relativity and Quantum Cosmology · Physics 2020-02-11 Manuel Hohmann , Christian Pfeifer , Nicoleta Voicu

We study the stochastic motion of active particles that undergo spontaneous transitions between two distinct modes of motion. Each mode is characterized by a velocity distribution and an arbitrary (anti-)persistence. We present an…

Statistical Mechanics · Physics 2023-07-07 M. Reza Shaebani , Heiko Rieger , Zeinab Sadjadi

We consider a multi component mixture of inert gas in the kinetic regime by assuming that the total number of particles of each species remains constant. In this article we shall illustrate our model for the case of two species. To account…

Analysis of PDEs · Mathematics 2018-10-23 Christian Klingenberg , Marlies Pirner , Gabriella Puppo

This paper reviews results on the scalar Boltzmann equation for a single-component polyatomic gas with continuous internal energy. For the space homogeneous problem, $L^1$-theory is established, for solutions with initial strictly positive…

Analysis of PDEs · Mathematics 2025-02-28 Ricardo Alonso , Milana Colic

This study investigates the steady Boltzmann equation in one spatial variable for a polyatomic single-component gas in a half-space. Inflow boundary conditions are assumed at the half-space boundary, where particles entering the half-space…

Analysis of PDEs · Mathematics 2026-02-03 Niclas Bernhoff , Stephane Brull , Eddie Wadbro

Non-ideal fluids are likely to be affected by the occurrence of pressure anisotropy effects, whose understanding for relativistic systems requires knowledge of the energy-momentum tensor. In this paper the case of magnetized jet plasmas at…

Plasma Physics · Physics 2023-06-22 Claudio Cremaschini