Patterns in hydraulic binary size sand grain ripples
نویسنده
چکیده
An experimental study of a sand bed submitted to a transient water shear flow in a vertical axis cylindrical container is reported. The appearance of spontaneous phase segregation in the spiral ripple patterns is shown. Larger grains are observed to segregate on the downstream part of the ripples, while the smaller ones segregate on the upstream part. The relative repose angles between sand species have no influence on the phase segregation. The formation of sedimentary structures is presented, and is the result of ripple climbing. The “sub-critical” or “super-critical” character of the lamination patterns is shown to depend on the rotation speed of the container.
منابع مشابه
Fe b 20 02 Patterns in hydraulic ripples with binary granular mixtures
An experimental study of a binary granular mixture submitted to a transient shear flow in a cylindrical container is reported. The formation of ripples with a spiral shape is observed. The appearance of phase segregation in those spiral patterns is shown. The relative grain size bewteen sand species is found to be a relevant parameter leading to phase segregation. However, the relative repose a...
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