Title
Computation and Optimal Perturbation of Finite-Time Coherent Sets for Aperiodic Flows Without Trajectory Integration
Abstract
Understanding the macroscopic behavior of dynamical systems is an important tool to unravel transport mechanisms in complex flows. A decomposition of the state space into coherent sets is a popular way to reveal this essential macroscopic evolution. To compute coherent sets from an aperiodic time-dependent dynamical system we consider the relevant transfer operators and their infinitesimal generators on an augmented space-time manifold. This space-time generator approach avoids trajectory integration and creates a convenient linearization of the aperiodic evolution. This linearization can be further exploited to create a simple and effective spectral optimization methodology for diminishing or enhancing coherence. We obtain explicit solutions for these optimization problems using Lagrange multipliers and illustrate this technique by increasing and decreasing mixing of spatial regions through small velocity field perturbations.
Year
DOI
Venue
2020
10.1137/19M1261791
SIAM JOURNAL ON APPLIED DYNAMICAL SYSTEMS
Keywords
DocType
Volume
coherent set,mixing,transfer operator,infinitesimal generator,unsteady flow,mixing optimization
Journal
19
Issue
ISSN
Citations 
3
1536-0040
1
PageRank 
References 
Authors
0.43
0
3
Name
Order
Citations
PageRank
Gary Froyland113017.19
Péter Koltai2193.87
Martin Stahn310.43