This component of the HEC-RAS modeling system is capable of simulating one-dimensional two-dimensional and combined one/two-dimensional unsteady flow through a full network of open channels, floodplains, and alluvial fans. One- and Two-Dimensional Unsteady Flow Simulation These situations include mixed flow regime calculations (i.e., hydraulic jumps), hydraulics of bridges, and evaluating profiles at river confluences (stream junctions) The momentum equation may be used in situations where the water surface profile is rapidly varied. Energy losses are evaluated by friction (Manning’s equation) and contraction/expansion (coefficient multiplied by the change in velocity head). The basic computational procedure is based on the solution of the one-dimensional energy equation. The steady flow component is capable of modeling subcritical, supercritical, and mixed flow regimes water surface profiles. The system can handle a full network of channels, a dendritic system, or a single river reach. This component of the modeling system is intended for calculating water surface profiles for steady gradually varied flow.

Sediment Transport/Movable Boundary Computations.

One- and Two-Dimensional Unsteady Flow Simulation.

In addition to these river analysis components, the system contains several hydraulic design features that can be invoked once the basic water surface profiles are computed. A key element is, that all four components use a common geometric data representation and common geometric and hydraulic computation routines. The HEC-RAS system contains several river analysis components for: (1) steady flow water surface profile computations (2) one- and two-dimensional unsteady flow simulation (3) movable boundary sediment transport computations and (4) water quality analysis.

Inundation mapping and animations of water propagation.

Tabulation and Graphical Displays of Input and Output Data.

The interface provides for the following functions: The main focus in the design of the interface was to make it easy to use the software, while still maintaining a high level of efficiency for the user. The user interacts with HEC-RAS through a graphical user interface (GUI). The following is a description of the major capabilities of HEC-RAS. HEC-RAS is designed to perform one and two-dimensional hydraulic calculations for a full network of natural and constructed channels. This software allows the user to perform one-dimensional steady flow, one and two-dimensional unsteady flow calculations, sediment transport/mobile bed computations, and water temperature/water quality modeling. Welcome to the Hydrologic Engineering Center’s (CEIWR-HEC) River Analysis System (HEC-RAS) website.

Run a flt file on hec ras