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Level set and the boundary condation

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Old   February 22, 2011, 21:25
Question Level set and the boundary condation
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AlvinXu
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I currently try to implement a level-set equation into OpenFOAM for a simulation of air-water effect on cable of cable stayed bridge,

first I solve the transport equation and use the zeroGradient boundary condition
solve
(
fvm::ddt(G)
+fvm::div(phi,G)
);
but the magnitude of fvc::grad(G) is not equal to one in the boundary cells, how can I deal with problem?

second , I solve the reinitialization equation whit steady state method and the Convergence condition is the average of mag(one-fvc::grad(G))=0,but as above, the boundary cell's gradient is not equal to 1,

how can I deal with this problem

Alvin

Last edited by alvin11; February 23, 2011 at 20:28.
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Old   February 24, 2011, 05:13
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Nima Sam
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i suggest instead of implement levelset method!!!!!! use redistance function to smooth interface and couple it with VOF method in openFoam
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Old   February 24, 2011, 05:53
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Duong A. Hoang
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Hi Nima,

I am using interFOAM to simulate capillary driven flow also. I found that the VOF method in OF produce quite bad curvature calculation. I am thinking of improving that by using couple level set and VOF or smoothed function. Could you please explain the term "redistance function to smooth interface" for me? Could you please also suggest any literatures for this "redistance function"?

Regards,

Duong
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Old   February 24, 2011, 06:55
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Nima Sam
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first of all!, if ur geometry is 3D
use interDyMFoam and use dynamic refinement may be it cures ur problem.
im also interested in coupling VOF and level set method in openFoam, i read some articles about but im some how busy to implement it my self now, so it would be great we both share our knowledge about it ,give me ur email i will send u those articles
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Old   February 24, 2011, 17:16
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Alvin,

I'm guessing that the outflow conditions on your redistancing method that are being applied at the boundaries are not consistent with the requirement that mag(Grad(G)) = 1.0
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Old   February 28, 2011, 04:37
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Matthias Voß
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this has already been done.
check out:http://www.uni-ulm.de/fileadmin/webs...les/CLSVOF.pdf

neewbie
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Old   February 28, 2011, 09:29
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Javier Basurco
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Dear Newbie,

May be you can send this article. I don't permission to access this server.

Thanks in advance

I look a forward to hearing from you

Respectfully
Ingenierias2003
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Old   February 28, 2011, 10:16
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Kathrin Kissling
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Hey,

pretty similar slides can be found here
http://web.student.chalmers.se/group...SlidesOFW5.pdf


Best

Kathrin
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Old   October 15, 2012, 19:31
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Alberto Passalacqua
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Is the code with CLSVOF (or similar approach coupling VOF and level-set) available?
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GeekoCFD - A free distribution based on openSUSE 64 bit with CFD tools, including OpenFOAM. Available as live DVD/USB, hard drive image and virtual image.
OpenQBMM - An open-source implementation of quadrature-based moment methods
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