Erosion of granular sediments by submerged impinging jets: Particle size effects and cohesion onset

This study investigates the erosion behavior and modeling of glass particle beds under impinging jet conditions, with a focus on particle size effects and the onset of cohesion. Ultrasonic profiling is implemented to scan and measure static crater profiles. Results indicate that particle size significantly affects crater dimensions, ring peak formation, and overall crater shape. The smallest glass particles ( d₅₀ = 35 μm) studied deviate from the trends in crater size, yield stress, and analytical modeling established using larger particles, indicating the onset of cohesion effects at this small particle size. The standard erosion parameter worked well for modeling cohesionless particles down to a certain size limit, beyond which cohesive forces become significant. A new parameter, Eτ based on particle critical shear stress, is introduced for erosion modeling in this study. The transition to cohesive behavior observed in the smallest glass particles is successfully accounted for using Eτ.