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Old   May 19, 2011, 12:33
Default Framework of the Mesh
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Hi,

I have mesh generated with Pointwise and this program generates circular mesh frameworks. This means that I can't specify inlet and outlet conditions, so I have the same conditions around the radius of the mesh.
I thought , the circular shape doesn't matter for simulating flows around airfoils.

Now I have doubts about this . I think it should matter, doesn't it ???
generating mesh is easy but I do not know how to change the framework of the mesh.
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Old   June 7, 2011, 10:27
Default problems due to framework of the mesh
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I have convergence problems due to the framework of mine mesh. I am trying to solve this issue with the icoFoam solver.

The framework of the mesh is represented with one patch, so I can't specify inlet/oulet separately ( this would solve my problem).

How should I define this one important patch ? I have used inletOutlet but the system doesn't converge.U file

Flow
{
type inletOutlet;
inletValue uniform (25 0 0);
value uniform (25 0 0);
}


p file

Flow
{
type outletInlet;
outletValue uniform 0;
value uniform 0;
}


How should I define this patch
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Old   June 7, 2011, 10:54
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Hello,
here is a long thread I started some time ago: Wing Aerodynamics Fluent OF 15 comparison Go through it, around post 35 I started to use a circular domain (generated with fluent, but this does not matter). There is a lot of information on how your bc should be set and some more about convergence issues. Exactly what you are looking for, aren't you ?

mad
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Old   June 8, 2011, 06:22
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Quote:
Originally Posted by maddalena View Post
Hello,
here is a long thread I started some time ago: Wing Aerodynamics Fluent OF 15 comparison Go through it, around post 35 I started to use a circular domain (generated with fluent, but this does not matter). There is a lot of information on how your bc should be set and some more about convergence issues. Exactly what you are looking for, aren't you ?

mad
Thank you for your reply.

Indeed it is almost what I want, only you have 3D case.

For testing I am using icoFoam and than I will go to kepsilon. I am now using inletOutlet for U and p. But still it is not converging. maybe there is a bug in openfoam version 1.7.1
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Old   June 9, 2011, 03:23
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Quote:
Originally Posted by Eren10 View Post
I am now using inletOutlet for U and p. But still it is not converging. maybe there is a bug in openfoam version 1.7.1
No bug! Read the thread a little bit more carefully: you should use zeroGradient for p!

mad
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Old   June 9, 2011, 16:06
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Quote:
Originally Posted by maddalena View Post
No bug! Read the thread a little bit more carefully: you should use zeroGradient for p!

mad

Thank you . I found an other very important problem: the trailing edge is perpendicular to the flow, which gives convergence problems. It seems Openfoam can't handle that part with normal mesh size . Maybe it is a good idea to choose an other airfoil.
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