The pressure drop in a pipe flow due to surface roughness is to be investigated for a wide range of flow rates that account for laminar, transitional and fully turbulent conditions.

This equipment measures pressure drop when water flows through a vertical pipe at various flow rates both laminar and turbulent. It consists of adjustable constant head water source of removable clear acrylic cylinder for laminar flow. Turbulent flow may be achieved by directly connecting the pipe to the Hydraulic Bench water supply. Flow rate can be controlled by a valve at outlet. A water manometer with a vent valve, a hand air pump and a mercury manometer are provided for measurement of pressure drop.5 Report Requirements:

1. Measure the pressure drop for an extensive range of pipe flow rates. Measure the volume flow rate using a graduated cylinder and a stopwatch.

2. For each test, calculate the Reynolds number (Re) and the head loss due to friction.

3. Hence determine the Fanning friction factor (f) from the Darcy-Weisbach equation (with Fanning friction factor):

f = h_l/[4(L/D).(V²/2g)]

4. Plot log(f) against log(Re) for all flow rates. Discuss.

5. Determine the critical or transitional Reynolds number. Comment on your results by comparing with theory and the Moody diagram attached.

6. Provide your detailed sample calculation.

7. Compare your laminar with your turbulent results. Discuss the dierences, if any, and calculate the measurements percentage error.