non positive volume
 

Dear all,
I have two files here.One of them(before wall) is before defining the skin of inner pipe as wall and the other is after that(Faces are associated to surface for this purpose) and the only difference between this two files is this association. the first one will export to fluent successfully while the second one will export to fluent with warning of non-positive volume.
Please help me. It 's made me confused.:confused:
https://hotfile.com/dl/239611896/c32..._wall.zip.html

https://hotfile.com/dl/239612371/894..._wall.zip.html

You do have negative elements, here is why:

https://dl.dropboxusercontent.com/u/35161486/why.JPG

I circled in blue the edges responsible for that, don't worry about it too much, minor problem.... come back to us if you can't fix it

Dear Ali,
Thank you so much for your reply.
Please help me to solve it.I am a bignner.Actually I couldn't understand what you mean.:(

you have a cylinder called wall , what'S inside it ??? is it empty ??

Thank you . :) .
Fluid flows in both cylinder.(Inside of the cylinder that called wall will be as interior and its skin will be only as wall)

no one can not help me?I have to solve my problem soon.:(
Please give me a solution.

:( :( :( :( :( :( :( :( :( :(

Thank you so much.Would you please explain for me how did you improve it? I have to do it myself