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-   -   tank sloshing - getting wrong pressure (http://www.cfd-online.com/Forums/cfx/87423-tank-sloshing-getting-wrong-pressure.html)

enghamed April 20, 2011 02:17

tank sloshing - getting wrong pressure
 
2 Attachment(s)
Hi,

I am running a two phase tank sloshing with mesh displacement.
My tank is 10m diameter, 7 meter height with water level of 6 meter. I have made a displacement of x=asinwt.
when I run it in the solver it says:"
+--------------------------------------------------------------------+
| Reference Pressure Information |
+--------------------------------------------------------------------+
Domain Group: Default Domain

Pressure has not been set at any boundary conditions.
The pressure will be set to 0.00000E+00 at the following location:
Domain : Default Domain
Node : 1 (equation 1)
Coordinates : (-3.53553E+00, 0.00000E+00,-3.53553E+00).
+--------------------------------------------------------------------+
| ****** Notice ****** |
| This is a multiphase simulation in a closed system. |
| A global correction will be applied to the volume fractions to |
| accelerate mass conservation. |
+--------------------------------------------------------------------+
Domain Group: Default Domain

Buoyancy has been activated. The absolute pressure will include
hydrostatic pressure contribution, using the following reference
coordinates: (-3.53553E+00, 0.00000E+00,-3.53553E+00)."

The coordinates which the solver mentions for the reference pressure is at the bottom of the tank. ( I don't know where I can specify the reference pressure in cfx-pre!)
I run it and after viewing the results I get a wrong pressure contour for pressure as you can see in the attached file. I need the correct value of pressure to calculate the force on the walls.
Can anyone help me out please?
I have attached the ccl file as well.
Regards

enghamed April 22, 2011 06:00

Can't anyone help me on this issue? I really need help. Please advise me. I would really appreciate it. Thanks

ghorrocks April 26, 2011 22:09

For an incompressible solver you need to set pressure somewhere. The pressure just offsets the pressure values and does not contribute to the solution at all. So the warning message is just saying pressure is being set at the location it specifies. If this location is not good then set another.

You can set the reference pressure on the domains tab.


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