Accession Number : ADA258068
Title : Depth-Averaged Numerical Modeling for Curved Channels
Descriptive Note : Final rept.
Corporate Author : ARMY ENGINEER WATERWAYS EXPERIMENT STATION VICKSBURG MS HYDRAULICS LAB
Personal Author(s) : Bernard, Robert S ; Schneider, Michael L
Report Date : Sep 1992
Pagination or Media Count : 48
Abstract : Without some correction for the interaction between lateral curvature and vertically nonuniform velocity, depth-averaged numerical models cannot predict the gradual migration of high velocity toward the outside of channel bends. Conventional depth-averaging does not account for the curvature-induced second- ary flow that gives rise to the migration. To remedy this deficiency, a secondary flow correction (SFC) has been developed and incorporated in the two- dimensional STREMR code. The secondary governing equation contains two-empirical coefficients, and these have been adjusted to make STREMR predictions agree with observed velocity profiles for a single 270-deg bend. Without further adjustment, the SFC yields comparable accuracy for multiple-bend predictions in two other channels with depth, curvature, and bottom friction different from the 270-deg case. This suggests that the SFC may be useful in general for bendways with small curvature, gentle side slope, and moderate bottom friction.
Descriptors : *MATHEMATICAL MODELS , *DEPTH , *CURVATURE , *CHANNELS(WATERWAYS) , VELOCITY , PREDICTIONS , MODELS , DISTRIBUTION , COEFFICIENTS , SLOPE , SECONDARY FLOW , NONUNIFORM , CORRECTIONS , CHANNELS , BOTTOM , FRICTION , EQUATIONS , FLOW , MIGRATION , DEFICIENCIES , PROFILES , INTERACTIONS , SECONDARY , HIGH VELOCITY , ACCURACY , TURBULENCE
Subject Categories : Hydrology, Limnology and Potamology
Distribution Statement : APPROVED FOR PUBLIC RELEASE