Water at 20°C is flowing in a 0.25-m-diameter and 120-m-long pipe which is inclined downward at a slope of 5%. The piezometric heads at the two ends are 1.6 m and 1.25 mas shown in Figure P7.13. Under...

Water at 20°C is flowing in a 0.25-m-diameter and 120-m-long pipe which is inclined downward at a slope of 5%. The piezometric heads at the two ends are 1.6 m and 1.25 mas shown in Figure P7.13. Under the Morris and Wiggerr criterion, what is the approximate thickness of the boundary layer in this case? Under the Singh criterion, what is the sublayer thickness? If chis pipe is made of galvanized iron, can it be considered a smooth pipe in this case?