Dam break test case

[Luca Milanesi]

Dear Colleagues,
I’m trying to build a dam break model based on literature test case. In particular I would be interested in reproducing a sudden dam break such as case 6A and 6B represented in the documentation RD51 (Benchmarking of the HEC-RAS Two-Dimensional Hydraulic Modeling Capabilities). This test case does not require boundary conditions and only an initial condition is needed. In particular the upstream (with respect to the dam) domain has an initial depth greater than = and the downstream one is dry. My question is: how can I reproduce a single domain with discontinuous initial condition?
I would avoid to build a model with two 2d domains connected by a 1d structure since I would lose the important information on the flow field across the dam.
Thanks
Luca Milanesi

[Anonymous]

Do it as a single 2D area. Create a 2D connector inside the 2D area to represent the dam. Make sure you select the 2D domain equation. Start the 2D area dry. Create a flow boundary condition on the upstream side and run it long enough to fill the reservoir up. If you are going to do a bunch of runs, it might save some computer time if you write out a restart file after filling the reservoir that you can then use for your initial conditions instead of having to fill it each time. So you should have a dam that has water on one side and is dry on the other side.

You could then add a dam break to the 2D connector and choose a breach formation time of a fraction of a second. As far as I know, that would cause the breach to completely form in a single time step and would be the same as an instantaneous dam break.

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