Prediction of Floating Solid Velocities in Unsteady Partially Filled Pipe Flow

摘要

The method of characteristics is applied to solve the unsteady partially filled pipe flow equations and to predict the velocity of floating solids assumed to travel at a fixed percentage of the local flow velocity. Experimental verification for the technique is provided for cylindrical solids in 100 mm diameter drainage pipe at a range of gradients from 1/40 to 1/150. The system upstream boundary conditions are shown to be capable of representation in terms of the inflow energy at the pipe entry section. Steady flow floating solid to flow velocity ratios are presented at 1/150 pipe gradient and further areas of experimental work to determine the variation of these ratios with pipe gradient and flow depth are identified.