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March 22, 2012, 03:19 |
free surface modelisation
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#1 |
New Member
Join Date: Feb 2012
Location: Nantes
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Dear all,
I am trying to model an open channel flow (free surface flow) in a pipe. The requirement is to obtain the 3D turbulent structure, including turbulence-driven secondary currents. I have tried innumerable strategies (combined inlet and seperate inlets....) with no luck in obtaining the expected results. In CCM+, I have defined a field function to fix the water level at the inlet (and used the same for initialization) but the free surface disapears.... Prob definition: Physics Models: -Multiphase VOF -Segregated Solver -Turbulent -> K-e realiz -Unsteady flow (Time step = 0.05s) BC's: -Combined Inlet: Velocity inlet [Magnitude = 0.5m/s)] -Outlet: Pressure Outlet -Turbulence specifications for Inlets and Outlets: TI = 10% Please have a look at the problem set up and sugest any change in strategy . Thank you |
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March 25, 2012, 04:10 |
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#2 |
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Join Date: May 2010
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I think separate inlets is the best option, or maybe it will work using the flat wave model for combined inlet.
How does the interface disappear? |
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March 25, 2012, 14:36 |
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#3 |
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Ryan Coe
Join Date: Jun 2010
Location: Albuquerque, NM
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Have you applied any control to the water level at the outlet?
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Ryan |
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April 1, 2012, 16:59 |
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#4 |
Senior Member
Join Date: Oct 2009
Location: Germany
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The water level at the outlet should be a result of the behaviour within the domain. Anyway, the pressure at the outlet should be set according to the expected water level.
Just a stupid question: Did you switch on gravity? Is the mesh fine enough? |
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April 10, 2012, 04:18 |
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#5 |
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Join Date: Feb 2012
Location: Nantes
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yes i switch on gravity,
i put my air with a velocity of 0.5m/s, the same for water. I attached a picture of the water level at the end of the simulation. I can't attache my report on the original format, my file exceeds the forum's limit . So i put the screenshots Last edited by hydraulic; April 10, 2012 at 04:40. |
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April 10, 2012, 04:21 |
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#6 |
New Member
Join Date: Feb 2012
Location: Nantes
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Thanks again,
Last edited by hydraulic; April 10, 2012 at 04:43. |
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