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2D Unsteady Flow
This is an advanced course in applying computer program HEC-RAS. The course provides participants with the knowledge to effectively use computer program HEC-RAS to analyze difficult hydraulic conditions in natural and constructed channels, utilizing one-dimensional and two-dimensional modeling techniques.
Topics covered in this course are listed below.
- Introduction to HEC-RAS 2D Modeling
- Terrain Data
- 2D Mesh Generation
- Land Classification Data
- Boundary and Initial Conditions
- Running a 2D Model
- Results Visualization
- Hydraulic Structures
- Dam and Levee Breaching
- Validation and Verification
A YouTube playlist for the entire class can be found here: HEC-RAS 2D Class (2021)
Additional Resources can be found on HEC's training page: HEC-RAS 2D Class
| Topic | Video | Supporting Documents |
|---|---|---|
Introduction to HEC-RAS 2D Modeling | ||
Overview of HEC-RAS 2D Modeling This presentation will discuss the many HEC-RAS 2D modeling capabilities of HEC-RAS 2D through example applications. | ||
Demonstration - Creating a 2D Model This presentation will take you through the steps of creating an HEC-RAS | ||
Sub-grid Bathymetry This presentation will discuss the use of the sub-grid technology in HEC-RAS that allows for detailed finite volume accounting and how water movement is controlled between 2D cells by their faces. | ||
Introduction to the 2D Equations This presentation discusses the underlying 2D hydraulic equations used in HEC-RAS. | ||
Terrain Data | ||
Creating a RAS Terrain This discussion introduces the basics in terrain model development and how to import elevation data to create a RAS Terrain. | ||
Workshop - Creating a RAS Terrain | ||
Terrain Modification This presentation shares the various way to perform terrain modifications on a RAS Terrain. | ||
Quick Demo - Introduction to Terrain Modification | ||
Workshop - Terrain Modification | ||
2D Mesh Generation | ||
Mesh Generation This presentation will discuss the basic concepts of creating a 2D Mesh in HEC-RAS. | ||
| Workshop - Mesh Generation | ||
Mesh Refinement This presentation will discuss improving and refining a 2D Mesh with Breaklines and Refinement Regions. | ||
| Workshop - Mesh Refinement | ||
Land Classification Data | ||
Manning's n Data This discussion will cover creating an Land Classification dataset for use with Manning's n values in RAS Mapper. | ||
| Demonstration - Manning's n Values and Calibration Regions | ||
| Workshop - Manning's n Data | ||
Boundary and Initial Conditions | ||
Boundary and Initial Conditions The different types of boundary conditions and establishing initial conditions will be discussed. | ||
Running a 2D Model | ||
Equation Selection A discussion on the use of Diffusion Wave and Full Shallow Water Equations in HEC-RAS is presented. A discussion of scenarios where the equations are appropriate is also provided. | ||
1D vs 2D Modeling This presentation discusses 1D vs 2D modeling and how to choose the appropriate modeling method. | ||
Computation Options The computation options available for model simulation. These include time step selection and various 2D computation options and parameters. | ||
| Workshop - Creating a Simple 2D Model | ||
| Workshop - 2D Model Refinement | ||
Advanced Computation Options More advance computation parameters will are discussed | ||
Results Visualization | ||
RAS Mapper An introduction to RAS Mapper is provided, specifically for visualizing HEC-RAS results. | ||
| Demonstration - RAS Mapper | ||
| Demonstration - Model Results in RAS Mapper | ||
Hydraulic Structures | ||
Combined 1D/2D Modeling This presentation will discuss creating a combined 1D/2D model. Specifically, you will learn how to perform modeling areas connected with a lateral structure behind a levee and be introduces to levee breaching capabilities. | ||
| Workshop - Combined 1D/2D Modeling | ||
Hydraulic Connections The use of hydraulic structures with a 2D Flow Area will be discussed. | ||
| Workshop - SA/2D Connections | ||
1D/2D Direct Connections This presentation will discuss how to hook a 1D reach directly into a 2D Flow Area as well as having a 1D reach come out of a 2D Flow Area. | ||
2D Bridges This presentation will discuss setting up a 2D Connection for modeling a bridge directly in a 2D Flow Area. | ||
| Workshop - 2D Bridge Hydraulics | ||
Dam and Levee Breaching | ||
Dam Breaching This presentation will discuss all of the ways dam breach scenarios can be modeled with 2D Flow Areas. You will also learn how to set up a hydraulic connections for modeling the dam, outlets, and breach parameters. | ||
| Workshop - Dam Breaching with 2D Flow Areas | ||
Selecting Dam Breach Parameters This presentation will discuss estimating dam breach parameters for modeling dam breach scenarios. | ||
Detailed Modeling | ||
Detailed Modeling This presentation will cover how to use the 2D Flow Area capability to perform very detailed multi-dimensional hydraulic analyses. | ||
Spatial Precipitation and Infiltration | ||
Spatial Precipitation and Infiltration This presentation/demonstration provides an introduction to developing an HEC-RAS model with spatial precipitation and modeling. | ||
3D Visualization | ||
3D Viewer This presentation provides a overview to using the HEC-RAS 3D Viewer. w/ Introduction to the 3D Viewer Demonstration | ||
HEC-RAS Model Validation and Verification | ||
| Validation and Verification of HEC-RAS | ||
| Benchmarking HEC-RAS | ||
| HEC was funded by the USACE SET program to edit this class and publish it online. |
