LES of a confined impinging jet reactor..
I am very very new to Openfoam. I have been using fluent to perform LES simulation for a some time now.
I have been trying to understand the tutorial files and it has not been that easy.
Here is what I did to get the case running.
Sorry for the long posting..
Hope to hear from you guys soon and thanks a tonne in advance..
I'll try to give you some answers so you can go on with your simulations:
1. I don't know what you mean by "adapting the grid" in Fluent, but I usually use fluentMeshToFoam from a .msh file and it works fine. After, be sure to change the types of boundaries in constant/polymesh/boundary.
2.1 Look at the constructor in the .C file of the model you want to use. When MUST_READ is specified, this variable is needed.
2.2 You can refer to the manual for boundary conditions types. I'm not really sure about plug flow, but it sounds like a fixedValue for U (uniform inlet). You can set your outlet as zeroGradient for U and fixedValue for p.
2.3 For your courant number, I suggest you add some correctors for your Piso loop (2 or 3).
3. For calculating values at each timestep, you can build a functionObject (refer to OpenFOAM-1.5/src/postProcessing/). You can also monitor variables using probes.
Good luck with your simulations and don't give up on OpenFOAM, it's well worth the effort!
i'm very new in OF.....
i've been looking for "must-read" entries in dynSmagorinsky.C file but i can't find any.....
i still do not know, what this model needs:
1) which files i have to supply
2) how i can choose a filter
3) where i can specify a heat transfer model
4) the near wall treatment....
every tutorial case in OF 1.7.1 is using the "oneEqEddy" model. so i have no pattern...
can someone help me? or tell me, where i can find help?
first, thanks for your replying.
1) you said, i can copy a tutorial case. but how do i know, which files a certain model needs? for example, the "oneEqEddy" model needs the "B" and "k" files, apparently. "dynSmagorinsky" doesn't need these files and they don't bother. but maybe it needs other files like "C" or "D"... so how do i get to know, WHICH files are needed IF needed?
4) i meant a near wall model. but after reading the user guide, i think this is specified in the 0/nut file....
P.S. Are you using the dynamic Smagorinsky model? If so, search for another thread I posted today on this topic. You might find my piece of code useful.
i wanted to use the dynSmagorinsky model.
but there are two problems, i think:
1) i need a turbulence model that corresponds to the paper of germano et al (1991). and i read before, that dynSmagorinsky model doesnt match germano fully.
2) i need to use a heat transfer model. but you told me, that i have to use a compressible solver to do so. i could take the rhoPisoFoam solver, but there is no dynSmagorinsky model for compressible solvers (OF user guide 1.7.1).
do you have a solution?
i'm going to read your other posts now :)
You can pull an implementation that uses local values of the coefficients from my git repository:
git clone git://github.com/AlbertoPa/dynLocalAverageSmagorinsky.git
Test it before using it however.
If you need an incompressible code, simply add the energy equation to pisoFoam. If you need a compressible code, you will have to implement the compressible version of the dynamic model (not the one from Germano's paper, which does not provide closures for the energy equation).
thanks for your support und patience...
can you explain me, how i can insert the energy equation:
fvm::ddt(rho, h) (--> remove, right?)
+ fvm::div(phi, h)
- fvm::laplacian(turbulence->alphaEff(), h)
in the pisoFoam.C file? copy and paste this and thats it??
i'm even worse in C++ than in OpenFoam....sorry
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