shadow elements
 

hi,

I am trying to simulate the flow in a cooling pipe of gas turbines.I have modelled it as two volumes on of the pipe and other outside turbine blades.The hole thru which the flow goes out of the pipe is a face on the pipe.I have ensured that there are no two coinciding surfaces.

when I export it to fluent,it creates one shadow zone on the outer pipe surface and grid check fails.Can somebody point out the problem in my model.

thanks and regards, santosh