English
Related papers

Related papers: Unified Gas-kinetic Wave-Particle Methods II: Mult…

200 papers

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

In this paper, a physics-oriented stochastic kinetic scheme will be developed that includes random inputs from both flow and electromagnetic fields via a hybridization of stochastic Galerkin and collocation methods. Based on the BGK-type…

Computational Physics · Physics 2021-03-17 Tianbai Xiao , Martin Frank

Gaseous flows show a diverse set of behaviors on different characteristic scales. Given the coarse-grained modeling in theories of fluids, considerable uncertainties may exist between the flow-field solutions and the real physics. To study…

Computational Physics · Physics 2021-05-05 Tianbai Xiao , Martin Frank

This paper introduces a time-domain harmonic balance unified gas-kinetic scheme (HB-UGKS) designed to simulate temporally periodic flows across all Knudsen regimes. The harmonic balance approach reformulates the periodic problem into a…

Fluid Dynamics · Physics 2026-05-06 Yuze Zhu , Hangkong Wu , Yufeng Wei , Kun Xu

In this paper, a third-order compact gas-kinetic scheme (GKS) on unstructured tetrahedral mesh is constructed for the compressible Euler and Navier-Stokes solutions. The time-dependent gas distribution function at a cell interface is used…

Computational Physics · Physics 2021-02-03 Xing Ji , Fengxiang Zhao , Wei Shyy , Kun Xu

In this paper, we present an advanced high-order compact gas-kinetic scheme (CGKS) for 3D unstructured mixed-element meshes, augmented with a geometric multigrid technique to accelerate steady-state convergence. The scheme evolves…

Computational Physics · Physics 2024-02-06 Hongyu Liu , Xing Ji , Yunpeng Mao , Yuan Ding , Kun Xu

In the study of rarefied gas dynamics, the discrete velocity method (DVM) has been widely employed to solve the gas kinetic equations. Although various versions of DVM have been developed, their performance, in terms of accuracy and…

Fluid Dynamics · Physics 2016-12-21 Peng Wang , Minh-Tuan Ho , Lei Wu , Zhaoli Guo , Yonghao Zhang

The M1 moment model for electronic transport is commonly used to describe non-local thermal transport effects in laser-plasma simulations. In this article, we propose a new asymptotic-preserving scheme based on the Unified Gas Kinetic…

Numerical Analysis · Mathematics 2025-04-09 Jean-Luc Feugeas , Julien Mathiaud , Luc Mieussens , Thomas Vigier

Unified gas kinetic scheme (UGKS) is an asymptotic preserving scheme for the kinetic equations. It is superior for transition flow simulations, and has been validated in the past years. However, compared to the well known discrete ordinate…

Fluid Dynamics · Physics 2016-08-31 Songze Chen , Zhaoli Guo , Kun Xu

As an extension of previous fourth-order compact gas kinetic scheme (GKS) on structured meshes (Ji et al. 2018), this work is about the development of a third-order compact GKS on unstructured meshes for the compressible Euler and…

Computational Physics · Physics 2019-02-15 Xing Ji , Fengxiang Zhao , Wei Shyy , Kun Xu

The gas dynamics under external force field is essentially associated with multiple scale nature due to the large variations of density and local Knudsen number. Single scale fluid dynamic equations, such as the Boltzmann and Navier-Stokes…

Fluid Dynamics · Physics 2017-10-31 Tianbai Xiao , Kun Xu , Qingdong Cai , Tiezheng Qian

The unified gas kinetic scheme (UGKS) was initially designed to address multiscale challenges in rarefied gas dynamics and then extended to radiative transfert theory, as described by BGK like relaxation models. In this work, we extend its…

Numerical Analysis · Mathematics 2025-07-08 Julien Mathiaud , Luc Mieussens , Nicolas Crouseilles

A Kinetic Inviscid Flux (KIF) is proposed for simulating incompressible and compressible flows. It is constructed based on the direct modeling of multi-scale flow behaviors, which is used in the Gas-Kinetic Scheme (GKS), the Unified…

Computational Physics · Physics 2020-09-23 Sha Liu , Junzhe Cao , Chengwen Zhong

A computationally accurate and efficient numerical method under a unified framework is crucial to various multi-scale scientific and engineering problems. So far, many numerical methods have encountered various challenges in efficiently…

Fluid Dynamics · Physics 2023-03-21 Rui Zhang , Sha Liu , Jianfeng Chen , Chengwen Zhong , Congshan Zhuo

In this paper an even higher-order compact GKS up to sixth order of accuracy will be constructed for the shock and acoustic wave computation on unstructured mesh. The compactness is defined by the physical domain of dependence for an…

Numerical Analysis · Mathematics 2020-10-20 Fengxiang Zhao , Xing Ji , Wei Shyy , Kun Xu

In 2010, the unified gas kinetic scheme (UGKS) was proposed by Xu et al . (A unified gas-kinetic scheme for continuum and rarefied flows, Journal of Computational Physics, 2010). In the past decade, many numerical techniques have been…

Computational Physics · Physics 2021-02-03 Yajun Zhu , Kun Xu

An efficient third-order discrete unified gas kinetic scheme (DUGKS) with efficiency is presented in this work for simulating continuum and rarefied flows. By employing two-stage time-stepping scheme and the high-order DUGKS flux…

Fluid Dynamics · Physics 2018-02-28 Chen Wu , Chang Shu , Baochang Shi , Zhen Chen

The stochastic particle method based on Bhatnagar-Gross-Krook (BGK) or ellipsoidal statistical BGK (ESBGK) model approximates the pairwise collisions in the Boltzmann equation using a relaxation process. Therefore, it is more efficient to…

Computational Physics · Physics 2018-08-14 Fei Fei , Jun Zhang , Jing Li , ZhaoHui Liu

A general framework for the development of high-order compact schemes has been proposed recently. The core steps of the schemes are composed of the following. 1). Based on a kinetic model equation, from a generalized initial distribution of…

Fluid Dynamics · Physics 2022-08-25 Fengxiang Zhao , Xing Ji , Wei Shyy , Kun Xu

For the two-layer shallow water equations, a high-order compact gas-kinetic scheme (GKS) on triangular mesh is proposed. The two-layer shallow water equations have complex source terms in comparison with the single layer equations. The main…

Numerical Analysis · Mathematics 2023-06-08 Fengxiang Zhao , Jianping Gan , Kun Xu