Roll waves and their generation criteria

ABSTRACT Pulsating waves (also known as roll waves) might occur on the free surface of extreme events like mud and debris flows, among others, usually intensifying caused damage. This technical note aims to inform about wave phenomenon developing in a free-surface laminar flow, analyze its generation criteria, centered concepts Froude number disturbance frequency. The complete linear stability analysis new depth-averaged model was proven useful theoretical tool determining criteria for non-Newtonian fluids. results showed that depends two criteria: first is associated minimum number, second related cut-off In addition, we have confirmed can be verified via numerical simulation based with full equations (Fluent software). Globally, emergence favored by properties flowing fluid fact frequency decreases along number. Lastly, both were tested order examine case study involving occurrence watershed.