Hi there, can anyone suggest the most accurate equation for a turbulent velocity profile in a pipe? I know standard fluid mechanics texts have them, but they are a bit too general. I want to compare the velocity profiles I am getting with my commercial code with the analytical approach. Thanks!

Do you mean instantaneous profile or time-averaged?

There are several choices depending on the references. Some people use: (u/u0)=(y/delta)^(1/7) and you get the displacement thickness: delta*=delta/8

(1). Schlichting's book,"boundary layer theory" has a chapter on "turbulent flow through pipes" which includes various formula for velocity profile, with test data.