Lagrangian coherent structures and the smallest finite-time Lyapunov exponent.
نویسندگان
چکیده
We point out that local minimizing curves, or troughs, of the smallest finite-time Lyapunov exponent (FTLE) field computed over a time interval [t(0), t] and graphed over trajectory positions at time t mark attracting Lagrangian coherent structures (LCSs) at t. For two-dimensional area-preserving flows, we conclude that computing the largest forward-time FTLE field by itself is sufficient for locating both repelling LCSs at t(0) and attracting LCSs at t. We illustrate our results on analytic examples, as well as on a two-dimensional experimental velocity field measured near a swimming jellyfish.
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ورودعنوان ژورنال:
- Chaos
دوره 21 2 شماره
صفحات -
تاریخ انتشار 2011