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We derive minimal discrete models of the Boltzmann equation consistent with equilibrium thermodynamics, and which recover correct hydrodynamics in arbitrary dimensions. A simple analytical procedure of constructing the equilibrium for the…

Condensed Matter · Physics 2009-11-07 Santosh Ansumali , Iliya V. Karlin , Hans Christian Öttinger

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

We study spatially non-homogeneous kinetic models for vehicular traffic flow. Classical formulations, as for instance the BGK equation, lead to unconditionally unstable solutions in the congested regime of traffic. We address this issue by…

Physics and Society · Physics 2019-07-22 Michael Herty , Gabriella Puppo , Sebastiano Roncoroni , Giuseppe Visconti

We propose a bound-preserving Runge-Kutta (RK) discontinuous Galerkin (DG) method as an efficient, effective and compact numerical approach for numerical simulation of traffic flow problems on networks, with arbitrary high order accuracy.…

Numerical Analysis · Mathematics 2014-07-14 Suncica Canic , Benedetto Piccoli , Jing-Mei Qiu , Tan Ren

The lattice Boltzmann method (LBM) is known to suffer from stability issues when the collision model relies on the BGK approximation, especially in the zero viscosity limit and for non-vanishing Mach numbers. To tackle this problem, two…

Computational Physics · Physics 2020-06-09 C. Coreixas , G. Wissocq , B. Chopard , J. Latt

Differential dynamic microscopy (DDM) typically relies on movies containing hundreds or thousands of frames to accurately quantify motion in soft matter systems. Using movies much shorter in duration produces noisier and less accurate…

Soft Condensed Matter · Physics 2024-11-05 Gildardo Martinez , Justin Siu , Steven Dang , Dylan Gage , Emma Kao , Juan Carlos Avila , Ruilin You , Ryan McGorty

To obtain explicit understanding of the behavior of dynamical systems, geometrical methods and slow-fast analysis have proved to be highly useful. Such methods are standard for smooth dynamical systems, and increasingly used for continuous,…

Quantitative Methods · Quantitative Biology 2023-10-19 Francesco Montefusco , Morten Gram Pedersen

Discrete diffusion models have emerged as powerful tools for high-quality data generation. Despite their success in discrete spaces, such as text generation tasks, the acceleration of discrete diffusion models remains under-explored. In…

Machine Learning · Computer Science 2024-12-09 Zixiang Chen , Huizhuo Yuan , Yongqian Li , Yiwen Kou , Junkai Zhang , Quanquan Gu

A conservative discrete velocity method (DVM) is developed for the ellipsoidal Fokker-Planck (ES-FP) equation in prediction of non-equilibrium neutral gas flows in this paper. The ES-FP collision operator is solved in discrete velocity…

Computational Physics · Physics 2019-09-25 Sha Liu , Ruifeng Yuan , Usman Javid , Chengwen Zhong

We introduce an $hp$-version discontinuous Galerkin finite element method (DGFEM) for the linear Boltzmann transport problem. A key feature of this new method is that, while offering arbitrary order convergence rates, it may be implemented…

Numerical Analysis · Mathematics 2024-07-18 Paul Houston , Matthew E. Hubbard , Thomas J. Radley , Oliver J. Sutton , Richard S. J. Widdowson

Kinetic schemes for compressible flow of gases are constructed by exploiting the connection between Boltzmann equation and the Navier-Stokes equations. This connection allows us to construct a flux splitting for the Navier-Stokes equations…

Numerical Analysis · Computer Science 2015-06-11 Praveen Chandrashekar

The recently proposed discrete unified gas kinetic scheme (DUGKS) is a finite volume method for deterministic solution of the Boltzmann model equation with asymptotic preserving property. In DUGKS, the numerical flux of the distribution…

Fluid Dynamics · Physics 2015-03-26 Lianhua Zhu , Zhaoli Guo , Kun Xu

In this paper, we develop a discrete unified gas kinetic scheme (DUGKS) for general nonlinear convection-diffusion equation (NCDE), and show that the NCDE can be recovered correctly from the present model through the Chapman-Enskog…

Computational Physics · Physics 2020-02-19 Jinlong Shang , Zhenhua Chai , Huili Wang , Baochang Shi

We adapt the Gradient Discretisation Method (GDM), originally designed for elliptic and parabolic partial differential equations, to the case of a linear scalar hyperbolic equations. This enables the simultaneous design and convergence…

Numerical Analysis · Mathematics 2019-10-28 Jérôme Droniou , Robert Eymard , T. Gallouët , R. Herbin

The discrete unified gas kinetic scheme (DUGKS) is a new finite volume (FV) scheme for continuum and rarefied flows which combines the benefits of both Lattice Boltzmann Method (LBM) and unified gas kinetic scheme (UGKS). By reconstruction…

Computational Physics · Physics 2024-05-29 Mingliang Zhong , Sen Zou , Dongxin Pan , Congshan Zhuo , Chengwen Zhong

Gas transport and other complex real-world challenges often require solving and controlling partial differential equations (PDEs) defined on graph structures, which typically demand substantial memory and computational resources. The Random…

Numerical Analysis · Mathematics 2025-06-16 Martín Hernández , Enrique Zuazua

The Lattice Boltzmann Method (LBM) has emerged as a powerful tool in computational fluid dynamics and material science. However, standard LBM formulation imposes some limitations on the applications of the method, particularly compressible…

Soft Condensed Matter · Physics 2025-03-14 Navid Afrasiabian , Colin Denniston

We introduce the concept of volume term adaptivity for high-order discontinuous Galerkin (DG) schemes solving time-dependent partial differential equations. Termed v-adaptivity, we present a novel general approach that exchanges the…

In this paper, a strongly mass conservative and stabilizer free scheme is designed and analyzed for the coupled Brinkman-Darcy flow and transport. The flow equations are discretized by using a strongly mass conservative scheme in mixed…

Numerical Analysis · Mathematics 2021-12-15 Lina Zhao , Shuyu Sun

Two discretizations of a 9-velocity Boltzmann equation with a BGK collision operator are studied. A Chapman-Enskog expansion of the PDE system predicts that the macroscopic behavior corresponds to the incompressible Navier-Stokes equations…

comp-gas · Physics 2008-02-03 Marc B. Reider , James D. Sterling