Geometry of intensive scalar mixing events in turbulence
نویسندگان
چکیده
Maxima of the scalar dissipation rate in turbulence appear in form of sheets and correspond with potentially most intensive scalar mixing events. Their cross-section thickness determines a local diffusion scale. The distribution of this scale is analysed with a fast multiscale clustering algorithm which is applied to very high-resolution simulation data. The thickness is found to be distributed across the whole viscous-convective Batchelor range and beyond. The dissipation maxima vary as the Kolmogorov (Batchelor) scale with respect to the Reynolds (Schmidt) number keeping the other parameter fixed in each case. The distribution of the thickness scales is traced back to the quasi-Gaussian distribution of the contractive short-time Lyapunov exponent of the flow. PACS numbers: 47.54.-r, 02.70.-c, 07.05.Pj
منابع مشابه
Geometry of intensive scalar dissipation events in turbulence.
The maxima of the scalar dissipation rate in turbulence appear in the form of sheets and correspond to the potentially most intensive scalar mixing events. Their cross section extension determines a locally varying diffusion scale of the mixing process and extends the classical Batchelor picture of one mean diffusion scale. The distribution of the local diffusion scales is analyzed for differen...
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