# Periodic boundary conditions

 Register Blogs Members List Search Today's Posts Mark Forums Read

 August 14, 2008, 12:08 Periodic boundary conditions #1 happy5jump Guest   Posts: n/a Hi everyone, I'm modling a 360 degrees cylinder I just want to use a 9 degrees slide to simulate the whole geometry. I set the left and right walls as periodic boundaries. Now I have two Questions: 1. how to set periodic boundary condition in FLUENT? There's no help in FLUENT about periodic boundary.... 2. What does this periodic boundary condition mean? Is there any relation with the calculation? Does periodic boundary mean it can simulate the real whole geometry? Thanks

 August 14, 2008, 17:09 Re: Periodic boundary conditions #2 red lemon Guest   Posts: n/a Both face sets represent the entire single periodic zone. Use the TUI command Grid>modify zone>make-periodic to create and slit periodic to remove. A periodic means flow through one face comes out of the other. For a regular periodic like turbo cases you need not set anything such as dP or flow in Define>periodics in the GUI. Fluent and Gambit see default periodics as conformal face sets but you can in fact define non conformal periodics using define>grid interface>make periodics. Hope that helps!

 August 14, 2008, 18:18 Re: Periodic boundary conditions #3 happy5jump Guest   Posts: n/a Thanks! One more thing I want to know is This is a 40 inlets geometry Can I just use 1 inlet ,1 outlet, and periodic boundary condition to samulate the whole geometry?

 August 18, 2008, 00:39 Re: Periodic boundary conditions #4 mAx Guest   Posts: n/a yes you can use only one inlet one your 9deg slice. But regarding the mesh, your both periodic faces have to be linked (eg: same mesh) Gambit won't you allow to set them as periodic if the surface meshes aren't the same.

 November 17, 2012, 19:34 help in periodic #5 New Member   fares Join Date: Nov 2012 Posts: 2 Rep Power: 0 I have the same problem I want to make the two opp walls at the inlet and outlet of a blade passage to be periodic how can i do so? in fluent 14

January 29, 2013, 16:06
#6
New Member

Join Date: Sep 2012
Posts: 4
Rep Power: 13
Quote:
 Originally Posted by red lemon ;152809 Both face sets represent the entire single periodic zone. Use the TUI command Grid>modify zone>make-periodic to create and slit periodic to remove. A periodic means flow through one face comes out of the other. For a regular periodic like turbo cases you need not set anything such as dP or flow in Define>periodics in the GUI. Fluent and Gambit see default periodics as conformal face sets but you can in fact define non conformal periodics using define>grid interface>make periodics. Hope that helps!
Hi,

I have a problem defining the periodic BC in FLUENT. I am simulating a wind turbine blade with one blade and 120 degree domain. but while I apply periodic BC in TUI , I got an error massage that main face and shadow face does not have same number of elements. one of my wall have 465 faces and the corresponding shadow face has 510 face.

How can I fix this problem? Is there any way to fix this problem in FLUENT ? I truly appreciate your suggestions.

Arif

 May 3, 2017, 00:36 #7 New Member   kshitiz Join Date: Apr 2017 Location: canada Posts: 3 Rep Power: 9 I am late but if you guys are wondering about the translational periodic boundary condition i have a solution. If you have a asymmetric geometry then before you run Make-periodic code in fluent you have to use a mesh match control to make equal number of mesh in adjacent faces. But while using mesh match control be sure to use arbitrary transformation. Thanks hope its helps