Transport based particle methods for the Fokker-Planck-Landau equation

1 code implementation • 16 May 2024 • Vasily Ilin, Jingwei Hu, Zhenfu Wang

We propose a particle method for numerically solving the Landau equation, inspired by the score-based transport modeling (SBTM) method for the Fokker-Planck equation.

An efficient dynamical low-rank algorithm for the Boltzmann-BGK equation close to the compressible viscous flow regime

no code implementations • 18 Jan 2021 • Lukas Einkemmer, Jingwei Hu, Lexing Ying

In this paper, we propose an efficient dynamical low-rank integrator that can capture the fluid limit -- the Navier-Stokes equations -- of the Boltzmann-BGK model even in the compressible regime.

Numerical Analysis Numerical Analysis Computational Physics

On the uniform accuracy of implicit-explicit backward differentiation formulas (IMEX-BDF) for stiff hyperbolic relaxation systems and kinetic equations

1 code implementation • 2 Dec 2019 • Jingwei Hu, Ruiwen Shu

To solve this type of problems, implicit-explicit (IMEX) Runge-Kutta or multistep methods have been widely used and their performance is understood well in the non-stiff regime ($\varepsilon=O(1)$) and limiting regime ($\varepsilon\rightarrow 0$).

Numerical Analysis Numerical Analysis

Quantification of thermally-driven flows in microsystems using Boltzmann equation in deterministic and stochastic contexts

1 code implementation • 3 May 2019 • Shashank Jaiswal, Aaron Pikus, Andrew Strongrich, Israel B. Sebastião, Jingwei Hu, Alina A. Alexeenko

When the flow is sufficiently rarefied, a temperature gradient, for example, between two walls separated by a few mean free paths, induces a gas flow---an observation attributed to the thermo-stress convection effects at microscale.

Computational Physics 76P05, 82B40, 82C40, 82D05, 35Q20, 65T50, 65M60, 65M70, 65Y05

A discontinuous Galerkin fast spectral method for multi-species full Boltzmann on streaming multi-processors

1 code implementation • 12 Mar 2019 • Shashank Jaiswal, Jingwei Hu, Julien K. Brillon, Alina A. Alexeenko

When the molecules of a gaseous system are far apart, say in microscale gas flows where the surface to volume ratio is high and hence the surface forces dominant, the molecule-surface interactions lead to the formation of a local thermodynamically non-equilibrium region extending few mean free paths from the surface.

Computational Physics 76P05, 82B40, 82C40, 82D05, 35Q20, 65T50, 65M60, 65M70, 65Y05

A discontinuous Galerkin fast spectral method for the multi-species Boltzmann equation

1 code implementation • 7 Mar 2019 • Shashank Jaiswal, Alina A. Alexeenko, Jingwei Hu

We introduce a fast Fourier spectral method for the multi-species Boltzmann collision operator.

Computational Physics Numerical Analysis Fluid Dynamics 76P05, 82B40, 82C40, 82D05, 35Q20, 65T50, 65M60, 65M70, 65Y05