English
Related papers

Related papers: A unified gas kinetic scheme for transport and col…

200 papers

A unified gas kinetic scheme (UGKS) for multi-scale and multi-component plasma transport is constructed. The current scheme is a direct modeling method, where the time evolution solutions from the Vlasov-BGK equations of electron and ion…

Computational Physics · Physics 2017-12-21 Chang Liu , Kun Xu

This study extends the Unified Gas-Kinetic Scheme (UGKS) and the Unified Gas-Kinetic Wave-Particle (UGKWP) method for electrostatic plasma modeling, ensuring the correct asymptotic limits with respect to both the Debye length and the mean…

Computational Physics · Physics 2025-12-18 Zhigang Pu , Kun Xu

In this paper, a unified gas-kinetic scheme (UGKS) with simplified multi-scale numerical flux is proposed for the thermodynamic non-equilibrium flow simulation involving the excitation of molecular vibrational degrees of freedom in all flow…

Fluid Dynamics · Physics 2023-02-08 Rui Zhang , Sha Liu , Chengwen Zhong , Congshan Zhuo

The Vlasov-Poisson-BGK (VPBGK) model is a kinetic model for describing the dynamics of collisional plasmas. Although various numerical schemes have been developed for it, a corresponding convergence theory has been absent. This paper fills…

Numerical Analysis · Mathematics 2026-05-11 Seung Yeon Cho , Sungsu Park , Seok-Bae Yun

In this paper, a unified gas kinetic scheme with adaptive velocity space (AUGKS) for multiscale flow transport will be developed. In near-equilibrium flow regions, particle distribution function is close to the Chapman-Enskog expansion and…

Computational Physics · Physics 2018-02-15 Tianbai Xiao , Kun Xu , Qingdong Cai

The unified gas-kinetic scheme (UGKS) is a direct modeling method for multiple scale transports. The modeling scale of the scheme is the mesh size and time step, and the ratios of the mesh size over particle mean free path or the time step…

Computational Physics · Physics 2019-05-01 Yajun Zhu , Chengwen Zhong , Kun Xu

In this paper, the unified gas-kinetic wave-particle (UGKWP) method is further developed for diatomic gas with the energy exchange between translational and rotational modes for flow study in all regimes. The multiscale transport mechanism…

Computational Physics · Physics 2021-07-07 Xiaocong Xu , Yipei Chen , Chang Liu , Zhihui Li , Kun Xu

The gas dynamics under gravitational field is usually associated with the multiple scale nature due to large density variation and a wide range of local Knudsen number. It is chal- lenging to construct a reliable numerical algorithm to…

Computational Physics · Physics 2017-02-01 Tianbai Xiao , Qingdong Cai , Kun Xu

The non-equilibrium gas dynamics is described by the Boltzmann equation, which can be solved numerically through the deterministic and stochastic methods. Due to the complicated collision term of the Boltzmann equation, many kinetic…

Computational Physics · Physics 2021-02-03 Xiaocong Xu , Yipei Chen , Kun Xu

The motion of a collisionless plasma - a high-temperature, low-density, ionized gas - is described by the Vlasov-Maxwell (VM) system. These equations are considered in one space dimension and two momentum dimensions without the assumption…

Analysis of PDEs · Mathematics 2016-04-18 Robert Glassey , Stephen Pankavich , Jack Schaeffer

The flow regime of micro flow varies from collisionless regime to hydrodynamic regime according to the Knudsen number. On the kinetic scale, the dynamics of micro flow can be described by the linearized kinetic equation. In the continuum…

Computational Physics · Physics 2020-05-27 Chang Liu , Kun Xu

Multiscale non-equilibrium physics at large variations of local Knudsen number are encountered in applications of aerospace engineering and micro-electro-mechanical systems, such as high-speed flying vehicles and low pressure of the…

Fluid Dynamics · Physics 2023-12-06 Yufeng Wei , Wenpei Long , Kun Xu

This paper presents a grid-free simulation algorithm for the fully three-dimensional Vlasov--Poisson system for collisionless electron plasmas. We employ a standard particle method for the numerical approximation of the distribution…

Numerical Analysis · Mathematics 2020-03-06 Torsten Keßler , Sergej Rjasanow , Steffen Weißer

The Vlasov equation is a nonlinear partial differential equation that provides a first-principles description of the dynamics of plasmas. Its linear limit is routinely used in plasma physics to investigate plasma oscillations and stability.…

Plasma Physics · Physics 2023-06-21 Abtin Ameri , Paola Cappellaro , Hari Krovi , Nuno F. Loureiro , Erika Ye

Nonequilibrium flows have been frequently encountered in various aerospace engineering applications. To understand nonequilibrium physics, multiscale effects, and the dynamics in these applications, an effective and reliable multiscale…

Fluid Dynamics · Physics 2024-07-23 Wenpei Long , Yufeng Wei , Kun Xu

The unified gas-kinetic scheme (UGKS) provides a framework for simulating multiscale transport with the updates of both gas distribution function and macroscopic flow variables on the cell size and time step scales. The multiscale dynamics…

Numerical Analysis · Mathematics 2018-11-20 Chang Liu , Yajun Zhu , Kun Xu

In this paper, a unified gas-kinetic wave-particle scheme (UGKWP) for the disperse dilute gas-particle multiphase flow is proposed. The gas phase is always in the hydrodynamic regime. However, the particle phase covers different flow…

Computational Physics · Physics 2022-03-14 Xiaojian Yang , Chang Liu , Xing Ji , Wei Shyy , Kun Xu

A discontinuous Galerkin method for approximating the Vlasov-Poisson system of equations describing the time evolution of a collisionless plasma is proposed. The method is mass conservative and, in the case that piecewise constant functions…

Plasma Physics · Physics 2011-10-04 R. E. Heath , I. M. Gamba , P. J. Morrison , C. Michler

The dynamics of collisionless plasmas can be modelled by the Vlasov-Maxwell system of equations. An Eulerian approach is needed to accurately describe processes that are governed by high energy tails in the distribution function, but is of…

The kinetic analyses of many-particle soft matter often employ many simulation studies of various physical phenomena which supplement the experimental limitations or compliment the theoretical findings of the study. Such simulations are…

Plasma Physics · Physics 2024-05-28 Allen Lobo , Vinod Kumar Sayal
‹ Prev 1 2 3 10 Next ›