After I run the Iterate and the computer run for several iterations, computer creases to run. It can read the following error message:

Error: Too many (3230) VOF sub-timesteps. The velocity field is probably diverging. Please check the solution, and reduce the time-step if necessary. Error Object: ()

What does this mean? My model is 3D, segregated, VOF, laminar and unsteady case. Thanks!

Best regards!

Hi!

Try it without "solve vof for evry iteration"...

I think it works ok then

mateus

Hi,

Your time step is too large. Divide yout time step dt with the # of VOF sub-timesteps (i.e. dt/3230). This will give you the value of VOF sub-timesteps. You should decrease your time step to a new value which should at most 100 times the value of VOF sub-timesteps.

Hi,

Fluent VOF has two kind of time step. It is that physical time step you specified and another is defined from Courant number(default is 0.25 in Multiphase Panel). In other words, Fluent doesn't use your specified time step size , directly. So in case of small Courant number is used, your problem will be good. Or use small time step size with default Courant number.

Thanks

FJ

Hi,

thank you all! I really appreciate your suggestion! i will try. thank you again!

best regards!

Benny