Fast and robust computation of coherent Lagrangian vortices on very large two-dimensional domains

TL;DR

This paper introduces a new automated method for efficiently computing various types of coherent Lagrangian vortices in large-scale two-dimensional flows, enabling analysis of complex real-world fluid dynamics problems.

Contribution

The authors present an improved, fully automated approach for detecting coherent vortices across large domains, overcoming previous computational limitations and enabling practical applications in real-world scenarios.

Findings

Successfully applied to turbulent flow parameter study

Effectively computed material barriers in global ocean data

Demonstrated robustness and efficiency on large-scale problems

Abstract

We describe a new method for computing coherent Lagrangian vortices in two-dimensional flows according to any of the following approaches: black-hole vortices [Haller & Beron-Vera, 2013], objective Eulerian Coherent Structures (OECSs) [Serra & Haller, 2016], material barriers to diffusive transport [Haller et al., 2018, Haller et al., 2019], and constrained diffusion barriers [Haller et al., 2019]. The method builds on ideas developed previously in [Karrasch et al., 2015], but our implementation alleviates a number of shortcomings and allows for the fully automated detection of such vortices on unprecedentedly challenging real-world flow problems, for which specific human interference is absolutely infeasible. Challenges include very large domains and/or parameter spaces. We demonstrate the efficacy of our method in dealing with such challenges on two test cases: first, a parameter study of a turbulent flow, and second, computing material barriers to diffusive transport in the global ocean.