4 Jan 2024

ERDC-PT: A Multidimensional Particle Tracking Model

Abstract: This report describes the technical engine details of the particle- and species-tracking software ERDC-PT. The development of ERDC-PT leveraged a legacy ERDC tracking model, “PT123,” developed by a civil works basic research project titled “Efficient Resolution of Complex Transport Phenomena Using Eulerian-Lagrangian Techniques” and in part by the System-Wide Water Resources Program. Given hydrodynamic velocities, ERDC-PT can track thousands of massless particles on 2D and 3D unstructured or converted structured meshes through distributed processing. At the time of this report, ERDC-PT supports triangular elements in 2D and tetrahedral elements in 3D. First-, second-, and fourth-order Runge-Kutta time integration methods are included in ERDC-PT to solve the ordinary differential equations describing the motion of particles. An element-by-element tracking algorithm is used for efficient particle tracking over the mesh. ERDC-PT tracks particles along the closed and free surface boundaries by velocity projection and stops tracking when a particle encounters the open boundary. In addition to passive particles, ERDC-PT can transport behavioral species, such as oyster larvae. This report is the first report of the series describing the technical details of the tracking engine. It details the governing equation and numerical approaching associated with ERDC-PT Version 1.0 contents.

26 Sep 2023

Linking the SEDLZJ Portable Standalone Library to the CMS Coastal Hydrodynamic Model

PURPOSE: This document describes the repackaging and linkage of the Sandia National Laboratories Environmental Fluid Dynamics Sediment Processes Code (SNL-EFDC-SEDZLJ), (Thanh et al. 2008). It was originally incorporated within a modified version of the US Environmental Protection Agency’s (USEPA) EFDC public-domain surface-water flow, sediment transport, and water-quality model developed by John Hamrick (Hamrick 1992) and its linkage to the ERDC-CHL-CMS hydrodynamic model. SNL-EFDC simulates flow and transport of sediment as bedload and suspended load. SNL-EFDC-SEDZLJ improves EFDC with updated sediment kinetics subroutines. Sediment erosion is calculated using data collected with a Sediment Erosion at Depth flume (SEDflume). SEDflume measures erosion rates as a function of shear stress and depth from relatively undisturbed cores taken directly from the sediment bed below the water body of interest. The use of SEDflume data provides more accurate sediment erosion rates that are directly input to the model.

24 Jan 2023

Swan Island Resilience Model Development; Phase I: Conceptual Model

Abstract: This report documents the development of an integrated hydrodynamic and ecological model to test assumptions about island resilience. Swan Island, a 25-acre island in Chesapeake Bay, Maryland, was used as a case study. An interagency, interdisciplinary team of scientists and engineers came together in a series of workshops to develop a simplified resilience model to examine the ability of islands to reduce waves and erosion and the impacts to nearby habitats and shorelines. This report describes the model development process and the results from this first key step: model conceptualization. The final conceptual model identifies four main components: vegetative biomass, island elevation, waves/currents, and sediment supply. These components interact to form and support specific habitat types occurring on the island: coastal dunes, high marsh, low marsh, and submerged aquatic vegetation. The pre-and post-construction field data, coupled with hydrodynamic ecological models, will provide predictive capabilities of island resilience and evaluations of accrued benefits for future island creation and restoration projects. The process and methods described can be applied to island projects in a variety of regions and geographic scales.

7 Jan 2022

Hydrodynamics in the Morganza Floodway and Atchafalaya Basin, Report 3: Phase 3; A Report for the US Army Corps of Engineers, MRG&P

Abstract: The Morganza Floodway and the Atchafalaya Basin, located in Louisiana west of the Mississippi River, were evaluated using a two-dimensional Adaptive Hydraulics model. Prior to this study, Phase 1 and 2 model studies were performed that indicated that the existing floodway may not be able to pass the Project Design Flood discharge of 600,000 cubic feet per second due to levee overtopping. In this study, all elevations of exterior and interior levees were updated with current crest elevations. In addition, the Phase 3 effort evaluated the sensitivity of the floodway’s flow capacity to variations in tree/vegetation density conditions. These adjustments in roughness will improve the understanding of the role of land cover characteristics in the simulated water surfaces. This study also provides a number of inundation maps corresponding to certain flows through the Morganza Control Structure.

29 Jan 2021

Mississippi River Adaptive Hydraulics Model Development and Evaluation, Commerce to New Madrid, Missouri, Reach

Abstract: A numerical, two-dimensional hydrodynamic model of the Mississippi River, from Thebes, IL, to Tiptonville, TN (128 miles/206 km), was developed using the Adaptive Hydraulics model. The study objective assessed current patterns and flow distributions and their possible impacts on navigation due to Birds Point New Madrid Floodway (BPNMF) operations and the Len Small (LS) levee break. The model was calibrated to stage, discharge, and velocity data for the 2011, 2015–2016, and 2017 floods. The calibrated model was used to run four scenarios, with the BPNMF and the LS breach alternately active/open and inactive/closed. Effects from the LS breach being open are increased river velocities upstream of the breach, decreased velocities from the breach to Thompson Landing, no effects on velocity below the confluence, and cross-current velocities greater than 3.28 ft/s (1.0 m/s) within 1186.8 ft (60 m) of the bankline revetment. Effects from BPNMF operation are increased river velocities above the confluence, decreased velocities from the BPNMF upper inflow crevasse (Upper Fuseplug) to New Madrid, cross-current velocities greater than 1.5 ft/s (0.5 m/s) only near the right bank where flow re-enters the river from the BPNMF lower inflow/outflow crevasse Number 2 (Lower Fuseplug) and St. Johns Bayou.

17 Jun 2020

PUBLICATION NOTICE: Theory, Formulation, and Implementation of The Cartesian and Spherical Coordinate Two-Dimensional Depth-Averaged Module of the Adaptive Hydraulics (AdH) Finite Element Numerical Code

Abstract: The US Army Engineer Research and Development Center, Coastal and Hydraulics Laboratory, has undertaken the development of the multi-module Adaptive Hydraulics (AdH) hydrodynamic, sediment, water quality, and transport numerical code. This report documents the mathematical formulation and numerical implementation of the two-dimensional depth-averaged module of AdH.