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Related papers: Improved multispecies Dougherty collisions

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A multi-species Fokker-Planck model for simulating particle collisions in a plasma is presented. The model includes various parameters that must be tuned. Under reasonable assumptions on these parameters, the model satisfies appropriate…

Mathematical Physics · Physics 2024-04-19 Evan Habbershaw , Cory D. Hauck , Jingwei Hu , Jeffrey R. Haack

The main concern of the present paper is the study of the multi-scale dynamics of thermonuclear fusion plasmas via a multi-species Fokker-Planck kinetic model. One of the goals is the generalization of the standard Fokker-Planck collision…

Numerical Analysis · Mathematics 2022-10-19 Francis Filbet , Claudia Negulescu

The linearized model collision operator for multiple species plasmas given by H. Sugama, T.-H. Watanabe, and M. Nunami [Phys.\ Plasmas {\bf 16}, 112503 (2009)] is improved to be properly applicable up to the highly collisional regime. The…

Plasma Physics · Physics 2020-01-08 Hideo Sugama , Seikichi Matsuoka , Shinsuke Satake , Masanori Nunami , Tomohiko Watanabe

A new analytically and numerically manageable model collision operator is developed specifically for turbulence simulations. The like-particle collision operator includes both pitch-angle scattering and energy diffusion and satisfies the…

Plasma Physics · Physics 2009-02-02 I. G. Abel , M. Barnes , S. C. Cowley , W. Dorland , A. A. Schekochihin

In dilute gas kinetic theory, model collision dynamics such as Bhatnagar-Gross-Krook (BGK) model is often used to get a better insight and numerical modelling. BGK model and its variants assume that highly nonlinear collision term can be…

Statistical Mechanics · Physics 2020-08-26 Samarth Agrawal , S. K. Singh , Santosh Ansumali

Generalising the work of Lenard and Bernstein, we introduce a new, fully relativistic model to describe collisional plasmas. Like the Fokker-Planck operator, this equation represents velocity diffusion and conserves particle number.…

Plasma Physics · Physics 2009-10-23 Adam Noble , David Burton

A new formulation for collisional kinetic theory is presented based on the use of Lie-transform methods to eliminate fast orbital time scales from a general bilinear collision operator. As an application of this new formalism, a general…

Plasma Physics · Physics 2009-11-10 Alain J. Brizard

We consider a multi component gas mixture with translational and internal energy degrees of freedom without chemical reactions assuming that the number of particles of each species remains constant. We will illustrate the derived model in…

Analysis of PDEs · Mathematics 2025-01-09 Marlies Pirner

Accurate modelling of the interaction between fast electrons and partially ionized atoms is important for evaluating tokamak disruption mitigation schemes based on material injection. This requires accounting for the effect of screening of…

Plasma Physics · Physics 2018-11-28 L Hesslow , O Embréus , M Hoppe , T C DuBois , G Papp , M Rahm , T Fülöp

Fokker-Planck equation with the velocity-dependent coefficients is considered for various isotropic systems on the basis of probability transition (PT) approach. This method provides the self-consistent and universal description of friction…

Plasma Physics · Physics 2009-11-07 S. A. Trigger

A general type of nonlinear Fokker-Planck equation is derived directly from a master equation, by introducing generalized transition rates. The H-theorem is demonstrated for systems that follow those classes of nonlinear Fokker-Planck…

Statistical Mechanics · Physics 2009-11-13 Veit Schwammle , Fernando D. Nobre , Evaldo M. F. Curado

A Fokker-Planck model for the interaction of fast ions with the thermal electrons in a quasi-neutral plasma is developed. When the fast ion population has a net flux (i.e. the distribution of the fast ions is anisotropic in velocity space)…

Plasma Physics · Physics 2020-01-08 Brian Appelbe , Mark Sherlock , Omar El-Amiri , Chris Walsh , Jeremy Chittenden

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

Particle-based stochastic approximations of the Boltzmann equation are popular tools for simulations of non-equilibrium gas flows, for which the Navier-Stokes-Fourier equations fail to provide accurate description. However, these numerical…

Numerical Analysis · Mathematics 2025-09-09 Veronica Montanaro , Lukas Netterdon , Manuel Torrilhon , Hossein Gorji

By considering the master equation of the partially asymmetric diffusion process on a one-dimensional lattice, the most general boundary condition (i.e. interactions) for the multi-species reaction-diffusion processes is considered.…

Statistical Mechanics · Physics 2009-11-11 M. Alimohammadi , Y. Naimi

We consider the mean field Fokker-Planck equation subject to nonlinear no-flux boundary conditions, which necessarily arise when subjecting a system of Brownian particles interacting via a pair potential in a bounded domain. With the…

Numerical Analysis · Mathematics 2022-03-30 R. D. Mills-Williams , B. D. Goddard , G. A. Pavliotis

Energetic electrons are of interest in many types of plasmas, however previous modeling of their properties has been restricted to the use of linear Fokker-Planck collision operators or non-relativistic formulations. Here, we describe a…

Plasma Physics · Physics 2016-11-28 A. Stahl , M. Landreman , O. Embréus , T. Fülöp

This paper considers a kinetic equation for an unbounded two-dimensional single species point vortex system. No axisymmetric flow is assumed. Using the kinetic theory based on the Klimontovich formalism, we derive a collision term…

Statistical Mechanics · Physics 2013-03-13 Yuichi Yatsuyanagi , Tadatsugu Hatori

This contribution presents a derivation of the steady-state distribution of velocities and distances of vehicles in freeway traffic which has been suggested for the evaluation of interaction potentials among vehicles (see preprint…

Statistical Mechanics · Physics 2007-05-23 Dirk Helbing , Martin Treiber

A generalized Fokker-Planck equation is derived to describe particle kinetics in specific situations when the probability transition function (PTF) has a long tail in momentum space. The equation is valid for an arbitrary value of the…

Statistical Mechanics · Physics 2011-08-15 A. A. Dubinova , S. A. Trigger
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