activity
20212026
most citedExtended Lattice Boltzmann Model

17 citations · 19 across the 15 of their papers we have counts for

collaborators

17 papers

physics.comp-ph2026

Residual Carleman lift for nonlinear lattice Boltzmann simulations

Ilya Karlin

Low-order Carleman embeddings replace nonlinear dynamics by a larger linear system, but truncation errors can accumulate even when the underlying nonlinear model is accurately appr…

physics.flu-dyn2026

One vertex generates the hard-sphere Boltzmann collision hierarchy

I. Karlin

The Boltzmann equation is the fundamental kinetic bridge between molecular mechanics and fluid behaviour. It converts binary encounters into the evolution of a velocity distributio…

cond-mat.stat-mech2026

Exact Collision Vertex for Stress and Heat Flux

Ilya Karlin

For the hard-sphere Boltzmann equation, we derive an exact nonlinear generating vertex for collisional stress and heat-flux production. The complete two-input Hermite hierarchy for…

math-ph2026

Bargmann-Fock Representation and Global Estimates for the Linearized Hard-Sphere Boltzmann Operator

Ilya Karlin

We study the linearized Boltzmann collision operator for three-dimensional hard spheres and reorganize the complete operator so that its angular and radial structures are explicit…

math-ph2026

Fock-Space Formulation of the Boltzmann Collision Operator for Maxwell Molecules

Ilya Karlin

We develop a representation-independent symmetric-Fock formulation of the nonlinear Boltzmann collision operator for Maxwell molecules. Starting from the standard velocity-space op…

physics.flu-dyn2026

Fock-Space Representation of the Lebowitz--Frisch--Helfand Kinetic Model

Ilya Karlin

We develop an exact Fock-space representation of the Lebowitz--Frisch--Helfand kinetic equation. The familiar square-root Maxwellian transformation is used only as a convenient sta…

physics.flu-dyn2026

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…

physics.flu-dyn2025

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…

math.AP2025

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…

math-ph2025

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…

math.DS2025

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…

physics.flu-dyn2025

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…

physics.flu-dyn2024

Exact Non-Local Hydrodynamics Predict Rarefaction Effects

Florian Kogelbauer, Ilya Karlin

We combine the theory of slow spectral closure for linearized Boltzmann equations with Maxwell's kinetic boundary conditions to derive non-local hydrodynamics with arbitrary accomm…

physics.flu-dyn2024

Transition time of a bouncing drop

Yahua Liu, Seyed Ali Hosseini, Cong Liu +4

Contact time of bouncing drops is one of the most essential parameters to quantify the water-repellency of surfaces. Generally, the contact time on superhydrophobic surfaces is kno…

physics.flu-dyn2023★ 2 cited

Rigorous Hydrodynamics from Linear Boltzmann Equations and Viscosity-Capillarity Balance

Florian Kogelbauer, Ilya Karlin

An exact closure for hydrodynamic variables is rigorously derived from the linear Boltzmann kinetic equation. Our approach, based on spectral theory, structural properties of eigen…

math-ph2023

Exact Hydrodynamic Manifolds for the Linear Boltzmann BGK Equation I: Spectral Theory

Florian Kogelbauer, Ilya Karlin

We perform a complete spectral analysis of the linear three-dimensional Boltzmann BGK operator resulting in an explicit transcendental equation for the eigenvalues. Using the theor…

physics.flu-dyn2021★ 17 cited

Extended Lattice Boltzmann Model

M. H. Saadat, B. Dorschner, I. V. Karlin

Conventional lattice Boltzmann models for the simulation of fluid dynamics are restricted by an error in the stress tensor that is negligible only for vanishing flow velocity and a…