TY - JOUR
T1 - Strong effect of weak diffusion on scalar turbulence at large scales
AU - Chertkov, M.
AU - Kolokolov, I.
AU - Lebedev, V.
N1 - Funding Information:
The work at Los Alamos National Laboratory was carried out under the auspices of the National Nuclear Security Administration of the U.S. Department of Energy under Contract No. DE-AC52-06NA25396. I.K. and V.L. also acknowledge partial support of the RFBR Grant No. 06-02-17408-a.
PY - 2007/10
Y1 - 2007/10
N2 - Passive scalar turbulence forced steadily is characterized by the velocity correlation scale L, injection scale l, and diffusive scale rd. The scales are well separated if the diffusivity is small, rd≪l,L, and one normally says that effects of diffusion are confined to smaller scales, r≪rd. However, if the velocity is single scale, one finds that a weak dependence of the scalar correlations on the molecular diffusivity persists to even larger scales, e.g., l≫r≫rd (E. Balkovsky , Pis'ma Zh. Eksp. Teor. Fiz. 61, 1012 (1995) [JETP Lett. 61, 1049 (1995)]). We consider the case of L≫l and report a counterintuitive result, namely the emergence of a new range of large scales, L≫;r≫l2/ rd, where the diffusivity shows a strong effect on scalar correlations.
AB - Passive scalar turbulence forced steadily is characterized by the velocity correlation scale L, injection scale l, and diffusive scale rd. The scales are well separated if the diffusivity is small, rd≪l,L, and one normally says that effects of diffusion are confined to smaller scales, r≪rd. However, if the velocity is single scale, one finds that a weak dependence of the scalar correlations on the molecular diffusivity persists to even larger scales, e.g., l≫r≫rd (E. Balkovsky , Pis'ma Zh. Eksp. Teor. Fiz. 61, 1012 (1995) [JETP Lett. 61, 1049 (1995)]). We consider the case of L≫l and report a counterintuitive result, namely the emergence of a new range of large scales, L≫;r≫l2/ rd, where the diffusivity shows a strong effect on scalar correlations.
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U2 - 10.1063/1.2793145
DO - 10.1063/1.2793145
M3 - Article
AN - SCOPUS:35748984965
SN - 1070-6631
VL - 19
JO - Physics of Fluids
JF - Physics of Fluids
IS - 10
M1 - 101703
ER -