how to run simple laminar 2d case

[Mubashir Ali]

hi All,
 
I wish to run a simple 2D airfoil case on code saturne. I prepared the 2D grid on gambit and made a neutral file.  But when i run Code saturne it gives me an error stating we cant find any volume cant proceed further.  below is the error which i found in listpre file
 
Warning ======= The mesh does not contain volume elements. We can go no further.
 
 
can anyone help me with this.... i need some help urgently
 
thnx
 
mubashir

[James McNaughton]

CS needs volumes and cannot run 2D. In gambit extrude your faces to be volumes and it should work. If the extrusion is one unit in length then 2D drag lift formulas will work but I've seen somewhere you should extrude only up to 10% of the chord length to avoid flow in your third-dimension - in which case you must take this into account.

[Mubashir Ali]

thnx for reply. But somewhr i read about 2d channel flow tutorial ..... i am not sure if the mesh used in this tutorial is actually 2D or 3D but its claimed to be 2D channel flow problem

[James McNaughton]

It will be a 3D mesh with only one cell in the span-wise direction and symmetry planes on both side faces. By making the cell thin enough you will have no cross-flow (although I generally go for unit thickness for simplicity and never have a problem).
James