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-   -   Level set and the boundary condation (https://www.cfd-online.com/Forums/openfoam/85316-level-set-boundary-condation.html)

alvin11 February 22, 2011 20:25

Level set and the boundary condation
 
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

nimasam February 24, 2011 04:13

i suggest instead of implement levelset method!!!!!! use redistance function to smooth interface and couple it with VOF method in openFoam

duongquaphim February 24, 2011 04:53

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

nimasam February 24, 2011 05:55

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 ;)

tabaer February 24, 2011 16:16

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

mvoss February 28, 2011 03:37

this has already been done.
check out:http://www.uni-ulm.de/fileadmin/webs...les/CLSVOF.pdf

neewbie

Ingenierias2003 February 28, 2011 08:29

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

kathrin_kissling February 28, 2011 09:16

Hey,

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


Best

Kathrin

alberto October 15, 2012 19:31

Is the code with CLSVOF (or similar approach coupling VOF and level-set) available?


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