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-   -   What outlet BC to use for a numerical wave tank with a velocity inlet? (http://www.cfd-online.com/Forums/fluent/84587-what-outlet-bc-use-numerical-wave-tank-velocity-inlet.html)

 JamesJ February 3, 2011 04:34

What outlet BC to use for a numerical wave tank with a velocity inlet?

Hello forum members,
I'm busy developing a 2D VOF model to depict the propagation of water waves in a numerical wave tank. I'm having boundary condition problems (I think :confused:).

Flow enters the domain through a velocity inlet on the left and I have a wall at the bottom. I have a pressure inlet at the top, as recommended on this forum and other sources. Why should one not use a pressure outlet here?

I want to absorb the generated wave on the right of the domain through numerical diffusion by letting the resolution of my grid get progressively worse and also prescribing the static pressure at the pressure outlet to that of the still water condition.

I set my backflow volume fraction at by my velocity inlet and pressure outlet on the right.

For some reason I'm getting a gale force wind in my air phase and crazy pressure conditions over my domain. If there is anyone out there that has experience with this type of simulation I would greatly appreciate any input you are willing to share with me.

James

 gxu2 August 8, 2012 17:43

Quote:
 Originally Posted by JamesJ (Post 293420) Hello forum members, I'm busy developing a 2D VOF model to depict the propagation of water waves in a numerical wave tank. I'm having boundary condition problems (I think :confused:). Flow enters the domain through a velocity inlet on the left and I have a wall at the bottom. I have a pressure inlet at the top, as recommended on this forum and other sources. Why should one not use a pressure outlet here? I want to absorb the generated wave on the right of the domain through numerical diffusion by letting the resolution of my grid get progressively worse and also prescribing the static pressure at the pressure outlet to that of the still water condition. I set my backflow volume fraction at by my velocity inlet and pressure outlet on the right. For some reason I'm getting a gale force wind in my air phase and crazy pressure conditions over my domain. If there is anyone out there that has experience with this type of simulation I would greatly appreciate any input you are willing to share with me. Thank you in advance, James

Hi, James

Now I am doing such simulation, but, unluckily, I encountered several problems like you, if you would like to communicate with me for VOF wave tank simulation, that is much better.