[Dunes de type « Barchanes » au laboratoire]
Nous montrons qu'il est possible d'étudier les dunes en laboratoire. Un tas de sable initial, soumis à un écoulement d'air chargé en sable, s'applatit et prend une forme qui rappelle celle d'une barchane. Nous proposons une loi d'évolution du profil et du sommet de la dune. Nous montrons que la dynamique de la dune est invariante de forme, et nous isolons cette forme invariante, « la fonction dune ».
We demonstrate the feasibility of studying dunes in a laboratory experiment. It is shown that an initial sand pile, under a wind flow carrying sand, flattens and gets a shape recalling barchan dunes. An evolution law is proposed for the profile and the summit of the dune. The dune dynamics is shown to be shape invariant. The invariant shape, the “dune function” is isolated.
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Mot clés : milieux granulaires, dunes, barchanes
Olivier Dauchot 1 ; Frédéric Lechénault 1 ; Cécile Gasquet 1 ; François Daviaud 1
@article{CRMECA_2002__330_3_185_0, author = {Olivier Dauchot and Fr\'ed\'eric Lech\'enault and C\'ecile Gasquet and Fran\c{c}ois Daviaud}, title = {{\textquotedblleft}Barchan{\textquotedblright} dunes in the lab}, journal = {Comptes Rendus. M\'ecanique}, pages = {185--191}, publisher = {Elsevier}, volume = {330}, number = {3}, year = {2002}, doi = {10.1016/S1631-0721(02)01447-X}, language = {en}, }
Olivier Dauchot; Frédéric Lechénault; Cécile Gasquet; François Daviaud. “Barchan” dunes in the lab. Comptes Rendus. Mécanique, Volume 330 (2002) no. 3, pp. 185-191. doi : 10.1016/S1631-0721(02)01447-X. https://comptes-rendus.academie-sciences.fr/mecanique/articles/10.1016/S1631-0721(02)01447-X/
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