9 papers
Monolithic kinetic algorithm for heterogeneous porous media systems using a continuous one-domain approach
Nikita O. Gusev, Ilya V. Karlin
We propose a lattice Boltzmann model (LBM) on standard lattices for simulating multi-dimensional, weakly compressible, isothermal flows within and around isotropic heterogeneous po…
A Note on Non-Hydrodynamic Solutions of Kinetic Systems
Florian Kogelbauer, Ilya Karlin
We show that the one-dimensional three-component Grad system admits solutions that violate the Chapman--Enskog scaling in Knudsen number. In particular, there exist solutions that…
Learning the Optimal Hydrodynamic Closure
Florian Kogelbauer, Candi Zheng, Ilya Karlin
We present the optimal hydrodynamic model for rarefied gas flows relative to a given kinetic model by combining the recent theory of slow spectral closure with machine learning tec…
Practical Kinetic Models for Dense Fluids
Ilya Karlin, Seyed Ali Hosseini
Nonlinear idempotent operator instead of a linear projection is introduced to derive kinetic models for dense fluids. A new lattice Boltzmann model for compressible two-phase flow…
On the Relation of Exact Hydrodynamics to the Chapman-Enskog Series
Florian Kogelbauer, Ilya Karlin
We demonstrate that the Chapman-Enskog series is locally equivalent to the exact spectral closure defined on slow kinetic eigenmodes in the limit of vanishing Knudsen number. We fu…
Dynamically Optimal Projection onto Slow Spectral Manifolds for Linear Systems
Florian Kogelbauer, Ilya Karlin
We derive the dynamically optimal projection onto the linear slow manifold from a temporal variational principle. We demonstrate that the projection captures transient dynamics of…