Winter 1982 (Final)

Water at 20

C is to be pumped through 30 metres of nominal 8 cm pipe (internal diameter 7.793cm) into an overhead reservoir. The volumetric flow rate of the liquid is 4 L / min.

(a) Is the flow laminar or turbulent? (Provide calculations to confirm your answer.)

(b) Calculate the pressure

(kPa) required at the outlet to the pump in order to supply water to the overhead reservoir at a rate of 4 litres/minute.

(c) Calculate the power (kW) rating for the pump.

Additional Data: At 20

C, the density and viscosity of water may be taken as 998.2 kg/

and 1.002 mPa s respectively.