FINMES error message!!
 

I have a fatal overflow error in the FINMES subroutine. Someone can help me? I try to change the resolution method, but don´t work.

Re: FINMES error message!!
 

Hi,

Try reducing the physical time step size.

Regards James

Re: FINMES error message!!
 

Thanks James! I reduce the phisical time step size to 10-5. SO I put to run and did the same error. May I change the size of the mesh grid? Do you know the best relation between the phisical time step and the mesh size? Thanks again. Regards Henry

Re: FINMES error message!!
 

Hi,

The appropraite physical time step size is largely independant of the grid. You should use a timescale representative of your problem.

If you are still getting FINMES errors in the first iteration then you almost certainly need to reduce the timestep further.

Glenn

Re: FINMES error message!!
 

Henry,

Many things could be wrong:

- Physical timescale may only be part of the problem. Typical rule of thumb is to use a maximum of 1/3 of the fluid residence time in through your device.

- Startup difficulties are typically initial guess related. How are you setting the initial guess for velocity and pressure for example??

- Perhaps you are running with turbulence on? Maybe you need to use the zero equation model to get a rough solution, and then restart with k-epsilon??

- Maybe your boundary conditions are too much at startup so you might need to ramp up your inlet total pressure or velocity as a function of iteration

As always, many things to go wrong, many things to try...

Neale

Re: FINMES error message!!
 

Thank you for the help Neale,I will try some changes and see what happen. Thank you again.