open TELEMAC-MASCARET The mathematically superior suite of solvers

Hi
I am trying to use TELEMAC 3D simulation wave action.At the end of the flume I set the boundary condition 444.
the velocity result at the end of the flume is normal for first 15 minutes,but the velocity turn from positive to negative after 15 minutes.
Is there something wrong in my setting?or how can i avoid this situation?

Can TELEMAC3D set sponge layer in the end of the flume?

Attachment are my cas file and result file.

thank you in advance!

Hello,

What type of flow is it? Subcritical or supercritical? Depending on the answer, changing the kind of outlet boundary conditions could help.

You can also:
- enlarge your domain,
- at the end of your outlet, artificially add a steep slope so that the flow becomes supercritical.

Hope this helps,

Chi-Tuan