Figure 4
From: Ultrasonic tracking of a sinking ball in a vibrated dense granular suspension
(a) Sketch of a ball sinking in a dense granular suspension. (b) Static friction coefficient µ0 and (c) effective viscosity ηeff versus vibration intensity, determined from the fit of traces z(t) in Figs 2a and 3a1,a2 by Eq. 4. Data are obtained with the different intruder size R = 4 mm (circles), 5 mm (triangles) and 7 mm (squares). The dotted line in (b) corresponds to a heuristic friction model (see text).
