To Implement A Clear-Water Supply System for Fine-Sediment Experiment in Laboratories

Fine sediment transport is currently attracting increasing attentions owing to its importance in the dynamics of sediment-contaminant interaction in the fluvial environment downstream of dams, which calls for more detailed and accurate flume experiments. However, because of inaccurate loading and undesired recirculation of fine sediment in the usual short laboratory flumes, such experiments are often unrepeatable and unreliable. In this technical note, we propose a new sediment feeder, to load dry sediment sample at the inlet, and a pressurized sediment filter, to screen the sediment out at the outlet, to implement a clear-water supply system for the flumes. It can improve fine sediment experiments not only by accurate loading but also through preventing undesired sediment recirculation, which can interfere and even modify the designated upstream input conditions. These devices have been constructed and tested, shown to be practical, simple and effective. Using them together can also provide a way to reclaim all the samples of experimental sediment that are of crucial importance for repeat and multiple tests for different contamination with a given sediment without losing the prescribed composition and other properties. This implementation is especially suitable for simulating fine particle affinity contaminant transport in fluvial turbulent flows in low sediment concentrations.