[irishdave]

Hello,

I am trying to implement a geometry-flexible LES inflow data generator (by Kempf, Klein, Janicka) in OpenFOAM. I have heard that several of the theories for inflow data generation for use in LES have already been implemented in OpenFOAM. I was wondering if anyone knows where I might be able to obtain the code for these implementations.

I have been experimenting with OpenFOAM for a while and have figured out quite a lot of what I need to know. I know how to find the inlet patch and determine the size of the velocity field at the inlet. I am struggling with obtaining the size information for the inlet from the actual mesh and the owner neighbour information for the internal faces within the inlet. I am sure there is an easier way to do this, I just haven't found it yet.

The procedure is documented in: A Kempf, M Klein, J. Janicka, Efficient Generation of Initial- and Inflow-Conditions for Transient Turbulent Flows in Arbitrary Geometries, Flow Turb. Combust. 2005 74: 67-84

I think that what is making it a lot harder is because I want my preProcessing tool to read the already generated mesh and then find the inlet from that to make it easier to use and so that it can work in any geometry.

If there is anyone could provide me with any information that might make this task easier I would be very grateful - we'll certainly make the new code available to the openFOAM community.

Thanks
David

[cedric_duprat]

Hi David,

I'm not sure there are several of the theories for inflow data generation for use in LES have already been implemented in OpenFOAM but, you can find some exemple in the LES discution and LES turbulent pipe flow.
Eugene "is writting" a code from a Schoppa and Hussain article, initialy used for channel and duct flow (Cf. article):

Schoppa & Hussain, "Coherent structure dynamics in near-wall turbulence", Fluid Dynamics Research, Vol 26, p 119-139, 2000.

Then, I remember that some one (forgot his/her name ... sorry) adapted this code in cylindrical coordinate (for pipe flow).

(I didn't check already it).

all these codes are avaiable in the forum.

I plan to add also a LES inflow generator (random vortex method from E. Sergent) but I'm quite busy now. I'll read your upper article, it's always usefull to developpe tools like that for LES.

Cedric

[tstovall]

Cedric,

I'm looking to implement the random vortex method from E. Sergent. Above you mention adding this feature; if it is complete I'd like to use it.

Thanks,

Tim

[cedric_duprat]

Hi Tim,

Still interrested in LES inflow condition ?
I plan to do now Klein boundary condition (Jou. Comp. Phys 186(2003) 652-665). Shortly, it can be usefull to generate inflow with RANS datas or experimental datas.
I'm doing it in the solver directly but after we can think of something more general for the community. It's easier doing like that.

If you are interresting of doing that together (or someone else), or if you have some comments, questions, let me now.

Cedric.

PS: I think it's easier to work together on new topic.

[IvanaS]

Hi Cedric,

I am interested in LES inflow boundary conditions in OpenFoam. what is your experience on that? I am particularly interested in Klein's digital filter method . Do you maybe have some experience on its implementation in OpenFoam?

Thank you very much.

Best regards,

Ivana