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


Full Text : https://apps.dtic.mil/dtic/tr/fulltext/u2/a258068.pdf


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
      Numerical Mathematics


Distribution Statement : APPROVED FOR PUBLIC RELEASE