Hey RAS Users. HEC just put out this very informative document that helps and guides the modeler with the decision between building a steady versus unsteady model, as well as when to go with a 1D, 2D, or 3D model. Modeler Application Guidance for Steady vs Unsteady, and 1D vs 2D vs 3D Hydraulic Modeling. […]
As a follow up to the just-posted Critical Depth Primer, I want to share a trick for getting HEC-RAS to compute and display critical depth at every cross section for unsteady flow. As I mentioned in the previous post, if you are running a steady flow model, there is an option to have RAS compute […]
The first version of HEC-RAS I ever used was Version 2.2 back in 1999. There are very few of us who actually used the first version of HEC-RAS which came out in 1995, but for those who do remember that, here’s an image showing the very first HEC-RAS Version 1.0: Version 1 was very simple, […]
What are the implications of having a cross section that is too short and doesn’t extend all the way out to the highest computed water surface elevation? Does it affect the results? Take this cross section for example. It is missing much of the left overbank (presumably). Image courtesy of Adam Bohnoff First of all, […]
Written by Chris Goodell, P.E., D. WRE | WEST ConsultantsCopyright © RASModel.com. 2010. All rights reserved.I was recently emailed this question regarding steady flow versus unsteady flow results: “My question is fairly basic. I have heard from a couple of other engineers that when flood levels are generated with usteady flows that it is typical […]