Hyperbolic Covariant Coherent Structures in Two Dimensional Flows
نویسندگان
چکیده
منابع مشابه
Hyperbolic Covariant Coherent Structures in Two Dimensional Flows
A new method to describe hyperbolic patterns in two-dimensional flows is proposed. The method is based on the Covariant Lyapunov Vectors (CLVs), which have the properties of being covariant with the dynamics, and thus, being mapped by the tangent linear operator into another CLVs basis, they are norm independent, invariant under time reversal and cannot be orthonormal. CLVs can thus give more d...
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It is shown: 1) that in two-dimensional, incompressible, viscous flows the vorticity-area distribution evolves according to an advection-diffusion equation with a negative, time dependent diffusion coefficient and 2) how to use the vorticity-streamfunction relations, i.e., the so-called scatter-plots, of the quasi-stationary coherent structures in order to quantify the experimentally observed c...
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ژورنال
عنوان ژورنال: Fluids
سال: 2017
ISSN: 2311-5521
DOI: 10.3390/fluids2040050