1 v 1 3 1 Ju l 1 99 8 Dissipation statistics of a passive scalar in a multidimensional smooth flow ∗
نویسندگان
چکیده
We compute analytically the probability distribution function P(ε) of the dissipation field ε = (∇θ)2 of a passive scalar θ advected by a d-dimensional random flow, in the limit of large Peclet and Prandtl numbers (Batchelor-Kraichnan regime). The tail of the distribution is a stretched exponential: for ε → ∞, lnP(ε) ∼ −(d2ε)1/3. PACS numbers: 47.10.+g, 47.27.-i, 05.40.+j
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