Forum: OpenFOAM Running, Solving & CFD
November 10, 2008, 17:58
|
|
Replies: 74
Views: 10,943
|
|
Forum: OpenFOAM Running, Solving & CFD
November 10, 2008, 14:04
|
|
Replies: 74
Views: 10,943
Hi BAN,
the reference is th
Hi BAN,
the reference is the following:
P. J. Oliveira, R. I. Issa, On the numerical treatment of interphase forces in two-phase flow, Numerical Methods in Multiphase Flows, Vol 185, ASME,...
|
|
Forum: OpenFOAM Running, Solving & CFD
October 29, 2008, 09:50
|
|
Replies: 74
Views: 10,943
Hi Danielle,
it seems to me
Hi Danielle,
it seems to me your simulation is not actually converging. What time step are you using? Keep in mind of the need to account for the drag time in the calculation of the time step...
|
|
Forum: OpenFOAM Running, Solving & CFD
October 28, 2008, 22:25
|
|
Replies: 74
Views: 10,943
Hi Danielle,
what do you me
Hi Danielle,
what do you mean with "unrealistic results"?
A completely explicit drag treatment is known to be slowly converging when a high drag coefficient is present. And actually only...
|
|
Forum: OpenFOAM Running, Solving & CFD
October 27, 2008, 19:40
|
|
Replies: 74
Views: 10,943
|
|
Forum: OpenFOAM Running, Solving & CFD
October 27, 2008, 14:18
|
|
Replies: 74
Views: 10,943
Hi Danielle,
I report some
Hi Danielle,
I report some references (have you access to them?) taken from the recent literature about bubble column simulations. As you can see from the titles, they deal with various topics,...
|
|
Forum: OpenFOAM Running, Solving & CFD
October 27, 2008, 10:52
|
|
Replies: 74
Views: 10,943
Hi Danielle,
I think you can
Hi Danielle,
I think you can use a "standard" drag law without blending, so that you need to specify only the mean bubble diameter, as done in many papers regarding bubble column simulations....
|
|
Forum: OpenFOAM Running, Solving & CFD
October 24, 2008, 16:56
|
|
Replies: 74
Views: 10,943
|
|
Forum: OpenFOAM Running, Solving & CFD
October 15, 2008, 15:49
|
|
Replies: 74
Views: 10,943
Hi,
when the UaEqn is defin
Hi,
when the UaEqn is defined you have:
UaEqn =
(
(scalar(1) + Cvm*rhob*beta/rhoa)*
(
fvm::ddt(Ua)
+ fvm::div(phia,...
|
|
Forum: OpenFOAM Running, Solving & CFD
October 13, 2008, 14:45
|
|
Replies: 74
Views: 10,943
Hi Danielle,
you can find t
Hi Danielle,
you can find the details in H. Rusche thesis, which can be downloaded from http://powerlab.fsb.hr/ped/kturbo/OpenFOAM/docs/HenrikRuschePhD2002.pdf
Only a comment about your...
|
|
Forum: OpenFOAM Running, Solving & CFD
March 5, 2007, 12:57
|
|
Replies: 74
Views: 10,943
Hello,
I read your comment on
Hello,
I read your comment on the bug report. The same observation is perfectly suitable for bubbling beds with a gas superficial velocity close to the minimum fluidization one.
About the...
|
|
Forum: OpenFOAM Running, Solving & CFD
March 4, 2007, 10:18
|
|
Replies: 74
Views: 10,943
Hello Rasmus,
the solution yo
Hello Rasmus,
the solution you proposed definetly works. I did the simulations I talked about in the bug-report and they're OK. The solution is more stable and I have no divergence problem....
|
|
Forum: OpenFOAM Running, Solving & CFD
February 6, 2007, 09:21
|
|
Replies: 74
Views: 10,943
I've an additional question to
I've an additional question too about the alpha equation. If the particle-particle force model is enabled (g0 != 0), an additional term is added to the phase continuity equation to implicitly make it...
|
|
Forum: OpenFOAM Running, Solving & CFD
January 31, 2007, 16:56
|
|
Replies: 74
Views: 10,943
Hello Guanghao,
the problems
Hello Guanghao,
the problems you noticed are due to the normal stress modulus (ppMagf) or, if you use the kinetic theory, to the granular pressure gradient in the momentum equation of the particle...
|
|
Forum: OpenFOAM Running, Solving & CFD
March 27, 2006, 19:01
|
|
Replies: 74
Views: 10,943
I've already implemented and g
I've already implemented and generalised that method, which seems to work well, even though it requires a small time step (10^-5).
I'm waiting for a paper acceptance and I'll release it.
In...
|
|
Forum: OpenFOAM Running, Solving & CFD
March 24, 2006, 09:45
|
|
Replies: 74
Views: 10,943
Yes. I'm working on cleaning t
Yes. I'm working on cleaning the code right now and on making a list of the changes I did.
I have some test case too which can be of interest, but I haven't extended the FoamX configuration...
|
|
Forum: OpenFOAM Running, Solving & CFD
March 24, 2006, 07:51
|
|
Replies: 74
Views: 10,943
What kind of problems do you h
What kind of problems do you have?
Can you complete the calculation, but the bubble shape is wrong? Or you can't obtain a converged solution?
Regards,
Alberto
|
|
Forum: OpenFOAM Running, Solving & CFD
March 24, 2006, 04:43
|
|
Replies: 74
Views: 10,943
Hello,
the granular pressure
Hello,
the granular pressure gradient is included in the pressure equation (pEqn.H):
if (kineticTheory.on())
{
phiDraga -= rUaAf*fvc::snGrad(kineticTheory.pa()/rhoa)*mesh.magSf();
} ...
|
|
Forum: OpenFOAM Running, Solving & CFD
March 9, 2006, 19:07
|
|
Replies: 74
Views: 10,943
Hello Oliver,
I can't downloa
Hello Oliver,
I can't download your attached file. Could you email it to me? My e-mail address should be visible in the forum.
However, the limitation of alpha between zero and one is managed...
|
|
Forum: OpenFOAM Running, Solving & CFD
February 21, 2006, 16:08
|
|
Replies: 74
Views: 10,943
To attach a file, insert the t
To attach a file, insert the text
\ attach{Description of your file}
without the space after \
The system will ask you to upload the file after you post the message. More information...
|
|
Forum: OpenFOAM Running, Solving & CFD
September 30, 2005, 18:08
|
|
Replies: 74
Views: 10,943
Hello, what solver settings we
Hello, what solver settings were used in the examples you showed me some month ago where you did the comparison between the algebraic and the differential transport equation of the granular energy? ...
|
|
Forum: OpenFOAM Running, Solving & CFD
September 25, 2005, 15:12
|
|
Replies: 74
Views: 10,943
I finally understood the probl
I finally understood the problem.
I started to work with a version of the solver in my user directory, then I moved to the version in the OpenFOAM main directory, without removing the libraries...
|
|
Forum: OpenFOAM Running, Solving & CFD
September 23, 2005, 18:17
|
|
Replies: 74
Views: 10,943
I replaced the Gidspow formula
I replaced the Gidspow formulation of g0 with the Carnahan and Starling (from Van Wachem phd thesis) one:
g0 = 1.0/(1.0 - alpha) + 3.0*alpha/(2.0*pow(1.0 - alpha, 2)) + pow(alpha,...
|
|
Forum: OpenFOAM Running, Solving & CFD
September 23, 2005, 13:20
|
|
Replies: 74
Views: 10,943
Thanks Mattijs.
#0 0x405eb
Thanks Mattijs.
#0 0x405eb246 in Foam::divide () from /home/alberto/OpenFOAM/OpenFOAM-1.2/lib/linuxGcc4Opt/libOpenFOAM.so
#1 0x0809e169 in Foam::divide<foam::fvpatchfield,>...
|
|
Forum: OpenFOAM Running, Solving & CFD
September 23, 2005, 12:59
|
|
Replies: 74
Views: 10,943
|
