Prediction of flow depth and sediment discharge in open channels

In recent years, attempts have been made to develop numerical models for unsteady flows in channels with sediment transport. The work presented in Reports KH-R-43A and KH-R-43B was conducted to analyze two essential ingredients of any numerical model: the relationship between the hydraulic variables (slope, depth, and velocity), and the predictor of sediment concentration. Report KH-R-43A presents a detailed analysis of the two components and examines their role in numerical modeling. Six hydraulic relationships and 13 sediment concentration predictors are examined and compared. New relationships are then developed which appear to be more accurate than the existing techniques. Finally, the new relationships are utilized in a numerical unsteady flow, moveable bed model which uses a four-point implicit finite difference solution scheme. The data base utilized in the first report is presented in Report KH-R-43B. The data base contains 7,027 records (5,263 laboratory records and 1,764 field records), in 77 data files. Not all records were used in the final analyses, but they have been included in an attempt to provide a historically complete set of alluvial channel observations. The material presented in these reports is essentially the same as the thesis submitted by the author in partial fulfillment of the requirements for the degree of Doctor of Philosophy. A common list of references, with data sources separated from other references, has been included in both reports.