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Search took 0.00 seconds. Search: Posts Made By: eugene
Forum: OpenFOAM June 9, 2010, 11:34
Replies: 32
Views: 18,166
Posted By eugene
If g is zero, the buoyancy force will be zero...

If g is zero, the buoyancy force will be zero too. The issue with poor meshes should go away, since there will be no hydrostatic pressure gradient and you will be left with something like simpleFoam...
Forum: OpenFOAM June 7, 2010, 10:30
Replies: 32
Views: 18,166
Posted By eugene
Hi Andrea, The problem is that grad(x) where...

Hi Andrea,

The problem is that grad(x) where x is a linearly varying field does not return a constant value field on distorted meshes. When you have a relatively high gradient, such as that...
Forum: OpenFOAM June 1, 2010, 05:54
Replies: 32
Views: 18,166
Posted By eugene
Hi Andrea, In general, for the default...

Hi Andrea,

In general, for the default solver implemented in 1.6.x, no. It is highly unlikely that you will be able to make a mesh for an automotive cockpit such that spurious numerical errors...
Forum: OpenFOAM May 27, 2010, 05:29
Replies: 32
Views: 18,166
Posted By eugene
Dear Valeria, The solvers are applicable to...

Dear Valeria,

The solvers are applicable to any case where the Boussinesq approximation can be justified, they just do not work very well on poor meshes. So if you have a perfect block structured...
Forum: OpenFOAM May 11, 2010, 04:26
Replies: 32
Views: 18,166
Posted By eugene
What would you like me to comment on? The...

What would you like me to comment on?

The div(phi)*T term prevents local errors due to non-consrvation of fluxes in unconverged velocity fields. It is zero at conergence.
Forum: OpenFOAM May 10, 2010, 04:31
Replies: 32
Views: 18,166
Posted By eugene
After a lot of trouble, I have found that the new...

After a lot of trouble, I have found that the new buoyantBousinesq line of solvers really are no good for real world cases. The main problem is the grad(p) and gravity density terms have to cancel...
Forum: OpenFOAM March 30, 2010, 07:03
Replies: 32
Views: 18,166
Posted By eugene
The problem is decomposePar does not load the...

The problem is decomposePar does not load the gravity dictionary, so it is not available when the boundary is constructed and therefore causes a fail. This is a general issue with boundaries that try...
Forum: OpenFOAM March 30, 2010, 04:17
Replies: 32
Views: 18,166
Posted By eugene
Hi Matthias, You boundary conditions look...

Hi Matthias,

You boundary conditions look fine for this case. Your problem must be somewhere else.
Forum: OpenFOAM March 29, 2010, 17:46
Replies: 32
Views: 18,166
Posted By eugene
Hi Andrea, I suggest you not use fixedValue...

Hi Andrea,

I suggest you not use fixedValue for pressure as outlet unless it is perpendicular to the direction of gravity. In the new solvers, p = P - pRef, so p will be stratified. Using a fixed...
Showing results 1 to 9 of 9

 
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