Escape Probability and Mean Residence Time in Random Flows with Unsteady Drift

TL;DR

This paper introduces methods to quantify fluid transport in random flows with unsteady drift using escape probability and mean residence time, supported by numerical algorithms and applied to tidal flow models.

Contribution

It develops numerical algorithms for calculating escape probability and mean residence time in unsteady random flows, addressing computational challenges and demonstrating application to tidal flows.

Findings

Effective numerical algorithms for escape probability and residence time.

Application to tidal flow model shows practical relevance.

Insights into fluid transport between different flow regimes.

Abstract

We investigate fluid transport in random velocity fields with unsteady drift. First, we propose to quantify fluid transport between flow regimes of different characteristic motion, by escape probability and mean residence time. We then develop numerical algorithms to solve for escape probability and mean residence time, which are described by backward Fokker-Planck type partial differential equations. A few computational issues are also discussed. Finally, we apply these ideas and numerical algorithms to a tidal flow model.