Large-scale anisotropy in scalar turbulence.
نویسندگان
چکیده
The effect of anisotropy on the statistics of a passive tracer transported by a turbulent flow is investigated. We show that under broad conditions an arbitrarily small amount of anisotropy propagates to the large scales where it eventually dominates the structure of the concentration field. This result is obtained analytically in the framework of an exactly solvable model and confirmed by numerical simulations of scalar transport in two-dimensional turbulence.
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عنوان ژورنال:
- Physical review letters
دوره 96 18 شماره
صفحات -
تاریخ انتشار 2006