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piccinini March 30, 2009 20:16

Plane channel flow
1 Attachment(s)

I'm a very begginer in OpenFOAM. I'm just trying to simulate a laminar plane channel flow using icoFoam.

I got the conditions from the analytical solution and fvSchemes and fvSolution from Cavity tutorial.
My problem is that Courant number keeps growing until explode.

The setup is attached.

Thanks in advance.

santos March 31, 2009 05:00


Here are two test-cases that may help you:

Jose Santos

piccinini March 31, 2009 20:14

Obrigado, Jose Santos!

I've got it to work. I had a problem in the BC and my time step was too high.

sven June 4, 2009 17:07

Hi Rodrigo,

I try to solve the same case and I think I also have some problems with my boundary conditions, especially with the one for the outlet. Could you please post your boundary conditions? That would be great! Thanks a lot!

svens June 5, 2009 10:17


I also started with this simple case to collect experiments in OF.

Copied the cavity tutorial and generated new mesh with new BC and initial conditions to solve with icoFoam a 2D channel case.

Now I am wondering - in folder .../case/0/ the dimension definition for pressure p?

-> dimensions [ 0 2 -2 0 0 0 0] -> this is no pressure!?

Anybody an idea about this background?

Thanks & regards

santos June 5, 2009 10:33


p is the kinematic pressure. If you multiply it by the density, you'll get Pascal units (kg/ms^2).

Jose Santos

piccinini June 5, 2009 12:19

1 Attachment(s)

You have my setup attached.
Hope it helps.

sven June 5, 2009 15:51


O.K. p is the kinematic pressure, I understand this. But what should I do if I don't want to set-up a dynamic pressure but a static pressure? If I just change the dimension, I get an error compiling it, which says, that the dimensions don't match. So, what do I have to do if I want to initialize my flowfield with a static pressure?

piccinini June 5, 2009 19:47

Hello Sven,

p is the static pressure divided by density (this is what Santos means with kinematic pressure).
You should not change units to set a static pressure, just divide the value by the constant density and set the resulting value.

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