Inundation Blowing Up

[jitraporn13]

Dear All

I'm trying to set up inundation problem in Gulf of Thailand.
It's blowing up in few steps as shown error below with "DIAG speed trouble 46.2305206398322"

For grid preparation: The minimum depth was -5m.
I also attached the log file of this case.

I dont know how to solve the problem. Please suggest some ideas.

Best Regards,
Tuk

[kate]

Have you tried a shorter timestep? It is blowing up so fast that is likely to be a contributing factor. After that, you need to be looking at how and where it is going bad. Wetting and drying problems can be tricky. I have gone so far as to manually edit the bathymetry in the wet-dry places to make it behave.

[wilkin]

Your log file shows you have set "nested" open boundary conditions for some variables but you have only one grid.

You have also mixed "gradient" and "closed" along the same boundary, so that can't be right.

Your initial conditions show a starting ubar and vbar of 4.5 and 5.7 m/s which is very fast so that is going to be a difficult spin-up. Plus, those values exceed the corresponding initial u,v max values, so they must be inconsistent.

ndtfast = 5 is a very small subdivision of the baroclinic time step. It is recommended not to go less than 20 to 30 for ndtfast.