The Suspension Of Sand By Waves

Abstract

Measurements are presented of the concentrations of sediment near rippled beds of sand in an oscillatory flow water tunnel. The measurements were made using a lightabsorption type of probe. The sediment was observed to be entrained from the bed in two ways. Firstly, bed-load carried over the crest is hurled in an, initially, thin jet over the lee vortex. Secondly, the vortex ejected at the end of each half cycle throws up a plume of sediment into the flow. The measurements were compared with results for bed-load transport over flat beds and also with predictions based on the defect-velocity distribution for rough beds.