activity
20202024
most citedConnecting the time evolution of the turbulence interface to coherent structures

32 citations · 59 across the 5 of their papers we have counts for

collaborators

8 papers

math.DS2024

Data-Driven Linearization of Dynamical Systems

George Haller, Bálint Kaszás

Dynamic Mode Decomposition (DMD) and its variants, such as extended DMD (EDMD), are broadly used to fit simple linear models to dynamical systems known from observable data. As DMD…

math.DS2024

Modeling Nonlinear Dynamics from Videos

Antony Yang, Joar Axås, Fanni Kádár +2

We introduce a method for constructing reduced-order models directly from videos of dynamical systems. The method uses a non-intrusive tracking to isolate the motion of a user-sele…

math.DS2024

Nonlinear Model Reduction to Temporally Aperiodic Spectral Submanifolds

George Haller, Roshan S. Kaundinya

We extend the theory of spectral submanifolds (SSMs) to general non-autonomous dynamical systems that are either weakly forced or slowly varying. Examples of such systems arise in…

physics.flu-dyn2023

Vorticity Alignment with Lyapunov Vectors and Rate-of-Strain Eigenvectors

Alex Encinas-Bartos, George Haller

We derive asymptotic estimates for the projection of the vorticity onto principal directions of material stretching in 3D flows. In flows with pointwise bounded vorticity, these es…

math.DS2023

Data-Driven Modeling and Forecasting of Chaotic Dynamics on Inertial Manifolds Constructed as Spectral Submanifolds

Aihui Liu, Joar Axås, George Haller

We present a data-driven and interpretable approach for reducing the dimensionality of chaotic systems using spectral submanifolds (SSMs). Emanating from fixed points or periodic o…

physics.flu-dyn2023★ 5 cited

Relative Fluid Stretching and Rotation for Sparse Trajectory Observations

Nikolas O. Aksamit, Alex P. Encinas-Bartos, George Haller +1

As most mathematically justifiable Lagrangian coherent structure detection methods rely on spatial derivatives, their applicability to sparse trajectory data has been limited. For…

physics.flu-dyn2021★ 22 cited

Quasi-Objective Coherent Structure Diagnostics from Single Trajectories

George Haller, Nikolas Aksamit, Alex P. Encinas Bartos

We derive measures of local material stretching and rotation that are computable from individual trajectories without reliance on other trajectories or on an underlying velocity fi…

physics.flu-dyn2020★ 32 cited

Connecting the time evolution of the turbulence interface to coherent structures

M. M. Neamtu-Halic, D. Krug, J. P. Mollicone +3

The surface area of turbulent/non-turbulent interfaces (TNTIs) is continuously produced and destroyed via stretching and curvature/propagation effects. Here, the mechanisms respons…