Question: The boundary layer which forms at the entrance to a circular pipe may be considered to behave like the boundary layer on a flat plate. Estimate the length needed to reach fully developed flow (i.e., for the edge of the boundary layer to reach the center line) for water at 68OF entering a pipe of 2-in. ID at a uniform velocity of
(a) 50 ft/s,
(b) 5 ft/s,
(c) 0.05 ft/s.