Flow Around and Forces on a Pipeline Near a Scoured Bed in Steady Current

Abstract

Flow around a pipeline placed initially on a flat, erodible bed was investigated at five characteristic stages of the progressive scour process in currents. The velocities, both in the streamwise direction and in the direction normal to the bed, were measured. A two-color flow visualization technique was used to detect the time-dependent flow structures. The forces on the cylinder were recorded simultaneously with the flow visualization. In the theoretical part of the study, a discrete vortex model (namely, the cloud-in-cell model) is employed to predict the flow. The early results appear to reveal the gross features of the flow shown by the experiments.