Author(s): Hridaya Bastola; Panayiotis Diplas
Linked Author(s): Hridaya Bastola
Keywords: Impulse concept Particle entrainment Wind tunnel experiments
Abstract: The understanding of the initiation of motion of non-cohesive surface sediments is fundamental in sediment transport processes in both fluvial and aeolian environments. In particular, the relative mobility of an exposed particle is important for improved comprehension of the particle arrangements achieved by water- and wind-worked sediments. In this study, we examine the effect of local geometry on the relative mobility of exposed particles at threshold conditions using wind tunnel experiments. Initiation of motion of surface particles subject to turbulent wall bounded flows occur during intermittent peak flow conditions where the fluid forces are sufficient to overcome resisting forces and last sufficiently long to ensure dislodgements. A dimensionless impulse parameter is used to compare the mobility of exposed particles in various arrangements. Our results indicate lesser mobility when exposed particles are smaller than the base particles and equal mobility when the exposed particles are larger than the base particles.
Year: 2025