[mohammad81]

Dear Foamer,

I want to model 2D laminar incompressible flow in a curved channel (a finite length of a channel), say something like cavity problem, except that the bottom and top walls are curved and fixed walls (the driving force is the pressure gradient).

I want to use cyclic boundary conditions for the problem.

Do you know what solver shall I use? icoFoam, simpleFoam, pimpleFoam, etc.
(A solver that can handle cyclic BC.)
I know channelFoam was a good one, but it is removed in OF 2.2.1 and my flow is laminar.

Thank you so much.
Mohammad

[Darth2013]

I also have a similar problem.

Anybody has an idea?
Thanks.
Steven

[lakeat]

Should be easy. Get back the channelFoam or do some combination with simpleFoam algorithm in case you want to do a steady RANS.

[Darth2013]

Hi Daniel,
Thanks for the reply.
I do not need RANS, since my flow is laminar.
1. But I do not understand your comment of getting back to ChannelFoam?!
2. Shall I also add a pressure gradient to the code? (since the driving force is pressure gradient) and if yes how?
3. I used cyclic BC for U and Fan BC for P. Do you think this is correct? I mean does this Fan BC creates a kind of pressure gradient pr I have to do something else?

Thanks so much.
Mohammad

[saadat66]

Dear mohammad81,

you can use ChannelFoam solver to simulate laminar flow in finite pipe. you should use channelFoam toturial test case and simply change LESModel in (your case directory/constant/LESProperties) from SGS model to "laminar". then run channelFoam command to run your case. but you see error messages and your run don't start. to overcome these errors you should add approprate divergence schemes to fvSchemes file(simply change nuEff to nu and etc).

I hope this help you.

[saadat66]

Dear Darth2013

if you use channelFoam solver to simulate your laminar test case with approprate modifications from previous post, you don't need to know any pressure gradient and also no need to change the main code. but you should know mean velocity in your test case (pipe, channel and etc). and simply add this parameter in transportProperties such as below:

Ubar Ubar [ 0 1 -1 0 0 0 0 ] ( 15.631 0 0 );

channelFoam solver calculate pressure gradient at every time step and write it in time directory.

I hope this help you.

Mohammad

[Z.Q. Niu]

Dear Mohammad,
Is Ubar the mean velocity at the inlet ?

[saadat66]

Dear Z.Q. Niu,
yes, Ubar is the mean velocity that you can calculate it from bulk Reynolds number (Re=H*Ub/nu).