Learning Forum

[fatima Zmim]

hello every one. I want to simulate (air and water) inside cylindre and this cylindre inside the box,but I have the divergence probleme for energy whethere i use multiphase model or not.I got this message when i run calculat "Turbulenve velocity limited to viscosity ratio of 1.000000e+05

plase help me to solve my probleme..

[SRP]

I suggest to try few things:

1) Refine the mesh where you there are sharp velocity gradients.

2) Try to adjust the relaxation factor.

3) If you are running a transient simulation, reduce the time step size and increase the number of iterations per time step.

4) You should also confirm that the turbulence model you are employing is appropriate for your particular issue.

Hope you find this useful.

Thank you

[fatima Zmim]

thank you for your reply, but on we can adjust relaxation factor?

yes i use transient simulation and my problem is i want to simulat water temperature for one day with time step 30 and time step size 30 with user deffin function. 

is the problem in time step size and is that necessiry to reduce the time step size for solve my problem

[SRP]

Hi,

Numerical stability and inaccuracy are influenced by time step size. Your results can be meaningless if you choose a really large step size because the resulting numerical approach is unstable. Reduce the time step to get a stable numerical technique since the fluid flow field often exhibits considerable oscillations.

Thank you

[fatima Zmim]

thank you for you reply