Good morning,
I am running a simulation with Level set Solver and Navier-Stokes; I have used the model of viewtopic.php?t=4366, but unfortunately, it gives me after 60 iterations the following error:
LevelSetTimestep: Levelset timestep 3.373E-17
WARNING:: ExecSimulation: Obsolete keyword > Timestep Function < , use > Timestep Size < instead
ERROR:: ExecSimulation: Timestep smaller than epsilon: 3.373E-17
STOP 1
How can I resolve this problem? I tried to increase the Courant number but without any improvement. Thanks in advance for your answes.
Regards,
Andrea
When maximum velocity goes very large then to fill the criteria v*dt<h the timestep becomes very small. So probably the routine is ok you just have your flow solution diverging.
With Elmer your best approach would be to lower the velocity. You might try to add the turbulent flow solver but not sure if it integrates well with level set. viewtopic.php?f=3&t=6995&hilit=turbulent
High velocity turbulent flow has not been a focus of Elmer. Most high velocity turbulent flow analyses use openfoam.
You could start there and determine the change. Turbulence depends on Reynolds's number which is a function of the velocity, pressure, and volume of the flow.
finer meshes, and smaller time steps, improve results when the flow starts to get turbulent.
Hi,
I also have tried to not consider the Courant number, but that does not produce any physical results. Eventually, I have reduced the velocity and Elmer always gives the same error. Are there any other numerical solutions that I can adopt?
Regards,
Andrea