Quasi-Objective Coherent Structure Diagnostics from Single Trajectories
arXiv:2101.05903 · doi:10.1063/5.0044151
Abstract
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 field. Both measures are quasi-objective: they approximate objective (i.e., observer-independent) coherence diagnostics in frames satisfying a certain condition. This condition requires the trajectory accelerations to dominate the angular acceleration induced by the spatial mean vorticity. We illustrate in examples how quasi-objective coherence diagnostics highlight elliptic and hyperbolic Lagrangian coherent structures even from very sparse trajectory data.
References in corpus (13)
- Defining Coherent Vortices Objectively from the Vorticity
- Lagrangian Descriptors: A Method for Revealing Phase Space Structures of General Time Dependent Dynamical Systems
- A Critical Comparison of Lagrangian Methods for Coherent Structure Detection
- Transport in time-dependent dynamical systems: Finite-time coherent sets
- Coherent Lagrangian vortices: The black holes of turbulence
- A Spectral Clustering Approach to Lagrangian Vortex Detection
- An analytic framework for identifying finite-time coherent sets in time-dependent dynamical systems
- Transport by Lagrangian Vortices in the Eastern Pacific
- Objective Eulerian Coherent Structures
- Coherent structure coloring: identification of coherent structures from sparse data using graph theory
- Polar rotation angle identifies elliptic islands in unsteady dynamical systems
- Objective barriers to the transport of dynamically active vector fields
- New Lagrangian diagnostics for characterizing fluid flow mixing
Cited by in corpus (6)
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- Quasi-Objective Eddy Visualization from Sparse Drifter Data
- Enhancing Transport Barriers with Swimming Microorganisms in Chaotic Flows
- Imaging-based 3D Particle Tracking System for Field Characterization of Particle Dynamics in Atmospheric Flows
- Relative Fluid Stretching and Rotation for Sparse Trajectory Observations