[isa982]

Hi,

My setup for icoFoam is as follows:

Mesh configuration:
Mesh configuration

The checkMesh.log.

fvSchemes
fvSolution

So what happened was, when I decreased my time step, my solution changes.

The following files are my U_magnitude at end time:
deltaT = 5e-3
deltaT = 5e-4
deltaT = 5e-5
deltaT = 5e-6

So by intuition, shouldn't all files have the same values?

Thank you for your help.

[wyldckat]

Greetings Isa,

What about the Courant Number for each simulation? What values did you get?

Best regards,
Bruno

[isa982]

The largest Courant number for all cases is not more than 0.4.

[wyldckat]

Hi Isa,

I'm guessing here, but I think you're seeing something similar to this case: http://www.cfd-online.com/Forums/ope...tml#post446350

The problem is that the mesh refinement you have at the inlet is creating a distortion in the fluid flow. You should have a uniform mesh, if you want good results.

Have a look at this blog post of mine for more ideas: OpenFOAM: Interesting cases of bad meshes and bad initial conditions

Best regards,
Bruno

[isa982]

Hi Bruno,

I think the boundary conditions might be the problem. So far I have tested several cases using large and uniform mesh and they all converge.

I am going to try smaller meshes and see what happens.

Thank you very much for your help.

[nanavati]

Originally Posted by isa982

Hi,

My setup for icoFoam is as follows:

Mesh configuration:
Mesh configuration

The checkMesh.log.

fvSchemes
fvSolution

So what happened was, when I decreased my time step, my solution changes.

The following files are my U_magnitude at end time:
deltaT = 5e-3
deltaT = 5e-4
deltaT = 5e-5
deltaT = 5e-6

So by intuition, shouldn't all files have the same values?

Thank you for your help.

Hello isa,

I have solved this backward step tutorial and validated with Available experimental data.

If you want to have a look on my set up files then I can share it with you. you may inbox me your email add.