Small-scale Behavior of Single Gravity-driven Fingers in an Initially Dry Fracture
نویسندگان
چکیده
Experiments investigating the behavior of individual, gravitydriven fingers in an initially dry, rough-walled analog fracture are presented. Fingers were initiated from constant flow to a point source. Finger structure is described in detail; specific phenomena observed include: desaturation behind the fingertip, variation in finger path, intermittent flow structures, finger-tip bifurcation, and formation of dendritic sub-fingers. Measurements were made of finger-tip velocity, finger width, and finger-tip length. Non-dimensional forms of the measured variables are analyzed relative to the independent parameters, flow rate and gravitational gradient.
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