Turbulent flow through hexagonal circular pipe
 

hi,
i am yogesh. i am new to fluent and gambit. i want to ask about turbulent flow through hexagonal pipe. Is it necessary to make boundary layer mesh fine on the pipe surface.
I heard something y+ in turbulent flow over a flat plat.
I want to know what is that y+ and why that is important in case of turbulent flow.
Please give me reply as fast as possible
Thank you
regards
yogesh