Effect of helicity on the effective diffusivity for incompressible random flows
نویسندگان
چکیده
منابع مشابه
Effect of helicity on the effective diffusivity for incompressible random flows.
The advection of a passive scalar by a quenched (frozen) incompressible velocity field is studied by extensive high precision numerical simulation and various approximation schemes. We show that second-order self-consistent perturbation theory, in the absence of helicity, perfectly predicts the effective diffusivity of a tracer particle in such a field. In the presence of helicity in the flow, ...
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ژورنال
عنوان ژورنال: Physical Review E
سال: 2001
ISSN: 1063-651X,1095-3787
DOI: 10.1103/physreve.63.061205