Model run is paused

EFDC+
1

Hello!
I’m trying to run a sediment transport model in 3D and I’m currently using the three-time level integration with a trapezoidal correction timing of 2. After a short time the model pauses and I receive the following message, “Fortran Pause - Enter Command(CR) or (CR) to continue”. First off, why does the model pause? Second, what type of command is the model looking for?

Thanks for your help.

Michael

2

Which EFDC Explorer version are you using ?

3

We think your error is due to one of the following issues:
1. efdc.inp C2: set ISMMC<0
2. Concentration of cohesive sediment SED(L,K,NS) < -1.0
3. Concentration of bed cohesive sediment SEDB(L,KBT(L),NS) < 0.

So in order to fix this problem you should :
1. Check initial and boundary conditions for cohesive sediment
2. Check the sediment parameters to ensure they are correct
3. Rerun the model
4. If the problem persists, try reducing the time step

Also, there is information about this in the file: ‘NEGSEDSND.OUT’

4

Thank you for your response. It seems that I end up with negative sediment concentrations. I will check all my initial and boundary conditions and run with a smaller time step.

Michael

5

I was able resolve my problem by changing from using a separate bed stress for cohesive and non-cohesive sediments to an aggregate bed shear. I’m now able to run my model in 3D.

Michael