5 papers · 1 filter
Objective detection of coherent vortices from instantaneous flow data
Tiemo Pedergnana, Florian Kogelbauer
Vortices are swirling regions of fluid that structure motion in gases and liquids across a wide range of scales, from laboratory-scale experiments to vast atmospheric currents. The…
An Objective Measure of Unsteadiness
Florian Kogelbauer, Tiemo Pedergnana
Unsteadiness lies at the heart of turbulent fluid dynamics, eddy formation and instabilities in flows thus making it central to both understanding and controlling fluid systems. In…
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…
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…
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…