Measurement of hydraulic and sediment transport variables in a small recirculating flume

Authors

  • R. E. Rathbun,

  • H. P. Guy


Abstract

An evaluation of techniques for measuring the hydraulic and sediment transport variables in a small recirculating flume showed that (1) the average depth of flow over a ripple bed could be determined adequately by measuring the difference between the water-surface elevation and the sand-bed elevation at a large number of positions and averaging the results; (2) the water-surface slope could be determined easily and accurately from a series of piezometers with taps positioned at 1-meter intervals along the flume center line; (3) the sediment transport rate was determined by passing all the water-sediment mixture through a trap covered with screen fine enough to hold the sand. The transport rate varied considerably (10-fold range) with respect to time. The following transport phenomena were noted: (1) there was no particle movement on the plane bed before ripple formation; (2) the mean velocity for cessation of particle movement (on the ripple bed) was about one-half that at which first movement occurred (on the plane sand bed).

Ancillary