P.V.Lukyanov On self-similar solutions for the problems of molecular and vortex turbulent diffusions |
Applied hydromechanics, Vol. 10 (82) ¹ 4, (2008) |
| It has been shown that observed in laboratory experiments self-similar solutions for azimuthal velocity and vertical vorticity have structures that are similar with two self-similar-analitycal solutions for turbulent diffusion of vortex. The turbulence is approximated by it's inertial interval characterised by quadratic growth in time for turbulent coefficients. The solutions for turbulent and molecular diffusions that correspond to first and third vorticity momenta are compared. Obtained for the first time, a snap-shot for the turbulent diffusion solution that corresponds to first momentum looks like Lamb vortex. The difference is the decay rates: t-3 for turbulent diffusion and t-1 for molecular one (Oseen vortex). A comparison of second solution for turbulent diffusion with the solution of "diffusive model" (molecular diffusion) points out the similarity of the solutions again. For rather large values of time thier rates of decay are t-6 and t-2 correspondently for turbulent and molecular diffusion. |
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| TEXT LANGUAGE: Russian |