2.6-3. Average Velocity for Mass Balance in Turbulent Flow. For turbulent flow in a smooth circular tube with a radius of R, the velocity profile varies according to the following expression at a Reynolds number of about 10³: max (R = 7) 17 where r is the radial distance from the center and the maximum velocity at the center. Derive the equation relating the average velocity (bulk velocity).. to a for an incompressible fluid. (Hint: The integration can be simplified by substituting z for R-r.) 49 Ans. 18 max 0.8170 60