15 Jun 2022

Foundational Principles in the Development of AdH-SW3, the Three-Dimensional Shallow Water Hydrodynamics and Transport Module within the Adaptive Hydraulics/Hydrology Model

Abstract: This report details the design and development of the three-dimensional shallow water hydrodynamics formulation within the Adaptive Hydraulics/Hydrology model (AdH-SW3) for simulation of flow and transport in rivers, estuaries, reservoirs, and other similar hydrologic environments. The report is intended to communicate principles of the model design for the interested and diligent user. The design relies upon several layers of consistency to produce a stable, accurate, and conservative model. The mesh design can handle rapid changes in bathymetry (e.g., steep-sided navigation channels in estuaries) and maintain accuracy in density-driven transport phenomena (e.g., thermal, or saline stratification and intrusion of salinity).

6 Jan 2022

Implementation of an Albedo-Based Drag Partition into the WRF-Chem v4.1 AFWA Dust Emission Module

ABSTRACT: Employing numerical prediction models can be a powerful tool for fore-casting air quality and visibility hazards related to dust events. However, these numerical models are sensitive to surface conditions. Roughness features (e.g., rocks, vegetation, furrows, etc.) that shelter or attenuate wind flow over the soil surface affect the magnitude and spatial distribution of dust emission. To aide in simulating the emission phase of dust transport, we used a previously published albedo-based drag partition parameterization to better represent the component of wind friction speed affecting the immediate soil surface. This report serves as a guide for integrating this parameterization into the Weather Research and Forecasting with Chemistry (WRF-Chem) model. We include the procedure for preprocessing the required input data, as well as the code modifications for the Air Force Weather Agency (AFWA) dust emission module. In addition, we provide an example demonstration of output data from a simulation of a dust event that occurred in the Southwestern United States, which incorporates use of the drag partition.

27 Aug 2021

Development of Three-Dimensional Wetting and Drying Algorithm for the Geophysical Scale Transport Multi-Block Hydrodynamic Sediment and Water Quality Transport Modeling System (GSMB)

Introduction: The Environmental Laboratory (EL) and the Coastal and Hydraulics Laboratory (CHL) have jointly completed a number of large-scale hydrodynamic, sediment and water quality transport studies. EL and CHL have successfully executed these studies utilizing the Geophysical Scale Transport Modeling System (GSMB). The model framework of GSMB is composed of multiple process models as shown in Figure 1. Figure 1 shows that the United States Army Corps of Engineers (USACE) accepted wave, hydrodynamic, sediment and water quality transport models are directly and indirectly linked within the GSMB framework. The components of GSMB are the two-dimensional (2D) deep-water wave action model (WAM) (Komen et al. 1994, Jensen et al. 2012), data from meteorological model (MET) (e.g., Saha et al. 2010 http://journals.ametsoc.org/doi/pdf/10.1175/2010BAMS3001.1), shallow water wave models (STWAVE) (Smith et al. 1999), Coastal Modeling System wave (CMS-WAVE) (Lin et al. 2008), the large-scale, unstructured two-dimensional Advanced Circulation (2D ADCIRC) hydrodynamic model (http://www.adcirc.org), and the regional scale models, Curvilinear Hydrodynamics in three dimensions-Multi-Block (CH3D-MB) (Luong and Chapman 2009), which is the multi-block (MB) version of Curvilinear Hydrodynamics in three-dimensions-Waterways Experiments Station (CH3D-WES) (Chapman et al. 1996, Chapman et al. 2009), MB CH3D-SEDZLJ sediment transport model (Hayter et al. 2012), and CE-QUAL Management - ICM water quality model (Bunch et al. 2003, Cerco and Cole 1994). Task 1 of the DOER project, “Modeling Transport in Wetting/Drying and Vegetated Regions,” is to implement and test three-dimensional (3D) wetting and drying (W/D) within GSMB. This technical note describes the methods and results of Task 1. The original W/D routines were restricted to a single vertical layer or depth-averaged simulations. In order to retain the required 3D or multi-layer capability of MB-CH3D, a multi-block version with variable block layers was developed (Chapman and Luong 2009). This approach requires a combination of grid decomposition, MB, and Message Passing Interface (MPI) communication (Snir et al. 1998). The MB single layer W/D has demonstrated itself as an effective tool in hyper-tide environments, such as Cook Inlet, Alaska (Hayter et al. 2012). The code modifications, implementation, and testing of a fully 3D W/D are described in the following sections of this technical note.

17 Aug 2021

The AFWA Dust Emission Scheme for the GOCART Aerosol Model in WRF-Chem v3.8.1

Abstract: Airborne particles of mineral dust play a key role in Earth’s climate system and affect human activities around the globe. The numerical weather modeling community has undertaken considerable efforts to accurately forecast these dust emissions. Here, for the first time in the literature, we thoroughly describe and document the Air Force Weather Agency (AFWA) dust emission scheme for the Georgia Institute of Technology–Goddard Global Ozone Chemistry Aerosol Radiation and Transport (GOCART) aerosol model within the Weather Research and Forecasting model with chemistry (WRF-Chem) and compare it to the other dust emission schemes available in WRF-Chem. The AFWA dust emission scheme addresses some shortcomings experienced by the earlier GOCART-WRF scheme. Improved model physics are designed to better handle emission of fine dust particles by representing saltation bombardment. WRF-Chem model performance with the AFWA scheme is evaluated against observations of dust emission in southwest Asia and compared to emissions predicted by the other schemes built into the WRF-Chem GOCART model. Results highlight the relative strengths of the available schemes, indicate the reasons for disagreement, and demonstrate the need for improved soil source data.

8 Jun 2021

New capabilities in CREATE™-AV Helios Version 11

Abstract: CREATE™-AV Helios is a high-fidelity coupled CFD/CSD infrastructure developed by the U.S. Dept. of Defense for aeromechanics predictions of rotorcraft. This paper discusses new capabilities added to Helios version 11.0. A new fast-running reduced order aerodynamics option called ROAM has been added to enable faster-turnaround analysis. ROAM is Cartesian-based, employing an actuator line model for the rotor and an immersed boundary model for the fuselage. No near-body grid generation is required and simulations are significantly faster through a combination of larger timesteps and reduced cost per step. ROAM calculations of the JVX tiltrotor configuration give a comparably accurate download prediction to traditional body-fitted calculations with Helios, at 50X less computational cost. The unsteady wake in ROAM is not as well resolved, but wake interactions may be a less critical issue for many design considerations. The second capability discussed is the addition of six-degree-of-freedom capability to model store separation. Helios calculations of a generic wing/store/pylon case with the new 6-DOF capability are found to match identically to calculations with CREATE™-AV Kestrel, a code which has been extensively validated for store separation calculations over the past decade.

8 Jun 2021

Summary of the SciTech 2020 Technical Panel on In Situ/In Transit Computational Environments for Visualization and Data Analysis

Link: http://dx.doi.org/10.21079/11681/40887This paper was originally presented at the American Institute of Aeronautics and Astronautics (AIAA) ScitTech 2020 Technical Panel and published online 4 January 2021. Funding by USACE ERDC under Army Direct funding.Report Number: ERDC/ITL MP-21-10Title: Summary of the SciTech 2020 Technical Panel on In

3 Jun 2021

In situ analysis and visualization to enable better workflows with CREATE-AV™ Helio

Abstract: The CREATE-AV™ Helios CFD simulation code has been used to accurately predict rotorcraft performance under a variety of flight conditions. The Helios package contains a suite of tools that contain almost the entire set of functionality needed for a variety of workflows. These workflows include tools customized to properly specify many in situ analysis and visualization capabilities appropriate for rotorcraft analysis. In situ is the process of computing analysis and visualization information during a simulation run before data is saved to disk. In situ has been referred to with a variety of terms including co-processing, covisualization, coviz, etc. In this paper we describe the customization of the pre-processing GUI and corresponding development of the Helios solver code-base to effectively implement in situ analysis and visualization to reduce file IO and speed up workflows for CFD analysts. We showcase how the workflow enables the wide variety of Helios users to effectively work in post-processing tools they are already familiar with as opposed to forcing them to learn new tools in order post-process in situ data extracts being produced by Helios. These data extracts include various sources of information customized to Helios, such as knowledge about the near- and off-body grids, internal surface extracts with patch information, and volumetric extracts meant for fast post-processing of data. Additionally, we demonstrate how in situ can be used by workflow automation tools to help convey information to the user that would be much more difficult when using full data dumps.

28 Apr 2020

PUBLICATION NOTICE: Lower Columbia River Adaptive Hydraulics (AdH) Model: Development, Water Surface Elevation Validation, and Sea Level Rise Analysis

Abstract: A numerical model of the Lower Columbia River, validated to water surface elevations, has been generated using the Adaptive Hydraulics (AdH) code. The model boundary conditions include an ocean tidal boundary and five inflows: the Lewis, Cowlitz, Willamette, and Sandy Rivers, and the Columbia River at Bonneville Lock and Dam. The model, which spans approximately 146 river miles, accurately reproduces water surface elevations measured in the field at several locations along the model domain. An examination of the AdH model’s Friction Library was also conducted. The Friction Library was used in this application to estimate the effects of pile dikes. Rather than model individual piles in the model mesh, the piles were modeled using the Friction Library’s submerged vegetation material type. Through testing of this application, it was determined that the Friction Library approach, which enhances model run time and efficiency, can accurately reproduce the global effects of pile dike fields. Additionally, the validated model was used to analyze three sea level rise (SLR) scenarios, which correspond to predicted SLR at Astoria, OR, at 50, 75, and 100 years from the present (0.5 meter [m], 1.0 m, and 1.5 m, respectively).

22 Apr 2020

PUBLICATION NOTICE: Nested Physics-Based Watershed Modeling at Seven Mile Creek: Minnesota River Integrated Watershed Study

ABSTRACT: The Minnesota River Basin (MRB) Integrated Study Team (IST) was tasked with assessing the condition of the MRB and recommending management options to reduce suspended sediments and improve the water quality in the basin. The Gridded Surface Subsurface Hydrologic Analysis (GSSHA) was chosen by the IST as the fine scale model for the Seven Mile Creek Watershed to help quantify the physical effects from best management practices within the MRB. The predominately agricultural Seven Mile Creek Watershed produces high total suspended solids and nutrients loads, contributing roughly 10% of the total load to the Minnesota River. GSSHA models were developed for a small experimental field research site called Red Top Farms, a Hydrologic Unit Code (HUC)-12 model for the entire Seven Mile Creek Watershed, a sub-basin of the Seven Mile Creek Watershed. After calibration, the resulting models were able to simulate measured tile drain flows, stream flow, suspended sediments, and to a lesser extent, nutrients. A selected suite of alternative land-use scenarios was simulated with the models to determine the watershed response to land-use changes at the small and medium scale and to test whether the type, size, and spatial distribution of land uses will influence the effectiveness of land management options.