Regarding face numbering.....
 

In the user guide of openfoam flow domain is discussed in same order of vertex numbering like fig 2.2 and also used same order of face numbering to define boundary. Is this universal rules for openFoam to follow same order for vertex and face numbering??? Or may I change the order of face numbering??? I have checked the blockMesh dict of a tutorial of heat transfer name buoyantCavity, here boundary face numbering is followed different order than fig 2.2 as I stated above. I am confused about it, any order of face numbering is ok???

For example: in fig 2.2:
(3 7 6 2)
(0 4 7 3)
(2 6 5 1)
(1 5 4 0)
(0 3 2 1)
(4 5 6 7)

but in buoyantCavity case,
(0 1 5 4)
(2 3 7 6)
(4 5 6 7)
(3 2 1 0)
(6 5 1 2)
(4 7 3 0)

but in ch. 5, face numbering is also different here

i think, for a geometry maintain a single rule (clockwise or anti-clockwise)

regard,
Ahmed Khatib
ahmed_khatibs@yahoo.co.in

thanks mr. ahmed. I actually confused, let see other comments...

Hello mukut,

just like ahmed said, you can ether define the faces or counterclockwise but you must be consistent and not have some faces clockwise and some counterclockwise.

Greets
Nigirim

Oh, I understand now. Thanks a lot.
Best regards
Mukut