[Le mélange est un processus d'agrégation]
Des expériences démonstratives suggèrent qu'un mélange scalaire agité relaxe vers l'uniformité à travers un processus d'agrégation. Les briques élémentaires sont des feuillets étirés qui se diluent dans le milieu en même temps qu'ils s'agrègent, construisant par là l'ensemble de la distribution de concentration de la mixture. Les cas considérés en particulier sont des mélanges en deux et trois dimensions, agités par des protocles très différents et qui pourtant donnent naissance aux mêmes distributions de concentration, stables par auto-convolution.
With the aid of several demonstration experiments, it is shown how a stirred scalar mixture relaxes towards uniformity through an aggregation process. The elementary bricks are stretched sheets whose rates of diffusive smoothing and coalescence build up the overall mixture concentration distribution. The cases studied, in particular, include mixtures in two and three dimensions, with different stirring protocols, which all lead to a family of concentration distributions stable by self-convolution.
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Mot clés : Turbulence, Mélange, Agitation, Diffusion, Agrégation
Emmanuel Villermaux 1 ; Jérôme Duplat 2
@article{CRMECA_2003__331_7_515_0, author = {Emmanuel Villermaux and J\'er\^ome Duplat}, title = {Mixing is an aggregation process}, journal = {Comptes Rendus. M\'ecanique}, pages = {515--523}, publisher = {Elsevier}, volume = {331}, number = {7}, year = {2003}, doi = {10.1016/S1631-0721(03)00110-4}, language = {en}, }
Emmanuel Villermaux; Jérôme Duplat. Mixing is an aggregation process. Comptes Rendus. Mécanique, Volume 331 (2003) no. 7, pp. 515-523. doi : 10.1016/S1631-0721(03)00110-4. https://comptes-rendus.academie-sciences.fr/mecanique/articles/10.1016/S1631-0721(03)00110-4/
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