Turbulent cyclic pipe flow, wall functions and y+
Sorry for the newbie question but I am just learning this stuff.
I have modeled a cyclic pipe in 3D with a modified simpleFoam solver to include a pressure gradient in the Ueqn to drive the flow. Question is; what is the appropriate value for y+ when using the kEpsilon model with wall functions? Re=38700 so its fully turbulent. My issue is that i would expect the desired y+ to be about ~10.6 corresponding to the intersection of the wall and log laws. After modifying my mesh to achieve this by placing the first node from the wall at y+=10.6 i dont get the desired effect when i plot u+ vs y+. Instead of a 'knee in the curve' at y+=10.6 its closer to y+=25. 
1 Attachment(s)
Attached is a graph of u+ vs y+ from my case.

I am like you newbie.
I am also interested in your this post. Please let me know about your findings. 
Hi clyde,
I am also doing turbulent pipe flow in OF. May I ask you that how do you get the mean velocity profile (for my pipe flow I don't know how to do field average in streamwise and circumferential directions)? It would be great if you can give me a hint on that and I really appreciate it. Thank you very much. Kind regards, Tony 
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