Development and Verification of Numerical Models for Predicting the Initial Fateof Dredged Material Disposed in Open Water. Report 2. Theoretical Developments and Verification Results

摘要

A numerical model called STFATE for computing the short-term fate of dredgedmaterial disposed in open water has been developed. STFATE builds upon work of earlier researchers to provide a more realistic simulation of real disposal operations from split-hull barges and multi-bin hopper dredges. New developments allow for multiple-convecting clouds and stripping of solids/ fluid from those clouds to better represent water column effects. Other developments include the use of the total energy approach for computing the bottom surge and computations that make the model more applicable at dispersive disposal sites. STFATE has been applied to simulate disposal tests conducted at a 1:50 scale in a large laboratory facility at the U.S. Army Engineer Waterways Experiment Station. Comparison of computed and measured results on decent and bottom surge speeds, bottom deposition, and suspended sediment concentrations have been made. The results show that STFATE can be used to reliably predict the fate of material disposed at open water disposal sites. However, an uncertainty analysis is needed to place accuracy bounds on model results. (AN).