Chapter 18, Problem 2P

1) A pelton wheel is used to produce hydroelectric power. The average radius of the wheel is 1.83 m, and the jet velocity is 100 m/s from a nozzle of exit diameter equal to 10 cm. What is the volume flow rate through the turbine in m3/s? a) 263.02 b) 0.801 c) 78.54 d) 0.785 2) A water pump increases the pressure of the water passing through it (see picture below). The flow is assumed to be incompressible. If the outlet diameter is less than inlet diameter, which of the following about outlet and inlet fluid velocity is correct? a) Vout < Vin b) Vout > Vin c) Vout = Vin d) cannot be determined

Water in a reservoir is flowing through a hydroelectric plant. The water level in the reservoir is 53 ft. The water level on the spillway is 3 feet and its width is 10 feet. The headloss is 10 ft. The flow leaving the reservoir is 500 cubic feet per second. What is the amount of head available to drive the turbine? 48.62 ft 31.38 ft 35.69 ft 44.31 ft

5. Water is pumped 14.5 km from a reservoir at elevation 30 m to another reservoir at elevation 70 m. The steel pipeline connecting the reservoirs has a nominal diameter of 1400 mm (the actual inside diameter is 1372 mm) with C = 90. If the flow is 1.18 m3/s, the pumping efficiency is 82%, and electricity costs $0.14/kWh. Assuming that the density of water is 1000 kg/m3, what will be the monthly power bill? Sketch the hydraulic and energy grade lines.