When a rivulet flows down an inclined plate, a meandering instability develops above a critical flow rate. We have performed experiments with water sliding down an inclined Mylar plate and determined the thresholds separating the different rivulet regimes: straight rivulets, stationary meanders, and dynamic rivulets. Dye visualizations have revealed interesting characteristics on the fluid velocity (dead zones, existence of reverse flow, etc…). At the transition straight/meandering, the mean velocity of the flow was found to drop drastically. The shape (amplitude, wavelength and radius of curvature) of the stationary meanders and its dependence on flow rate has been extracted from the experiments for increasing flow rates. Both the meandering threshold observed and the curvature radius of the meanders are interpreted by a simple model combining centrifugal forces, surface tension effects and wetting hysteresis. The rivulet flow is also shown to be highly hysteretic since the shape of the meanders remains unchanged when one decreases flow rate, and this until the rivulet eventually breaks into drops. Consequently, the straight rivulet regime can only be obtained for increasing flow rates
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