Abstract
A simple iterative approach for solving a set of implicit kinetic moment equations is proposed. This implicit solve is a key component in the IMEX discretization of the multi-species Bhatnagar-Gross-Krook (M-BGK) model with nontrivial collision frequencies depending on individual species temperatures. We prove that under mild time step restrictions, the iterative method generates a contraction mapping. Numerical simulations are provided to illustrate results of the IMEX scheme using the implicit moment solver.
| Original language | English |
|---|---|
| Pages (from-to) | 881-907 |
| Number of pages | 27 |
| Journal | SIAM Journal on Numerical Analysis |
| Volume | 63 |
| Issue number | 2 |
| DOIs | |
| State | Published - 2025 |
Funding
This manuscript has been authored, in part, by UT-Battelle, LLC, under contract DE-AC05-00OR22725 with the U.S. Department of Energy (DOE). The U.S. Government retains and the publisher, by accepting the article for publication, acknowledges that the U.S. Government retains a nonexclusive, paid-up, irrevocable, worldwide license to publish or reproduce the published form of this manuscript, or allow others to do so, for U.S. Government purposes. DOE will provide public access to these results of federally sponsored research in accordance with the DOE Public Access Plan (https://energy.gov/downloads/doe-public-access-plan).
Keywords
- fixed point iterative solvers
- implicit time stepping strategies
- kinetic theory
- moment equations
- multi-species BGK
- rarefied gas dynamics