Prediction of Flow Depth and Sediment Discharge in Open Channels

Channel Design;Friction Factor;Hydraulics;Open Channel Flow;Sediment Transport;Sediment Transport Formula;Sedimentation;Unsteady Flow

Brownlie, William Robert ; Brooks, Norman H.

University:California Institute of Technology

Department:Engineering and Applied Science

关键词: Channel Design;    Friction Factor;    Hydraulics;    Open Channel Flow;    Sediment Transport;    Sediment Transport Formula;    Sedimentation;    Unsteady Flow;   

Others  :  https://thesis.library.caltech.edu/5064/3/brownlie_wr_1982.pdf

美国|英语

来源: Caltech THESIS

【 摘 要 】

In recent years attempts have been made to develop numerical models for unsteady flows in channels with sediment transport. This work 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.

A data base containing 7027 records (5263 laboratory records and 1764 field records) in 77 data files was assembled and is provided (Appendix B). The data base was used to examine existing relationships and to develop new ones. Six existing hydraulic relationships are reworked and examined. Detailed statistical analyses are provided for 13 existing techniques for predicting sediment concentration.

Relying heavily on statistical analysis of dimensionless groups, new relationships have been developed. The new hydraulic relationship solves for flow depth for upper and lower regime flow separately and then provides a method for determining which flow regime one might expect. The new method for predicting sediment transport, which is easy to use, appears to be more accurate than the 13 existing methods, and suggests that complex procedures for calculating concentration are not warranted.

A four-point implicit finite difference scheme has been presented to demonstrate the feasibility of applying the new hydraulic and sediment relationships to a numerical solution of the differential equations.