Hot water, initially at 200°F and 14.7 psia, is piped through a series system that is 1,000 ft long and contains 12 elbows, a heat exchanger, and a plug disk glove valve. Schedule 40 pipe of 3-in. nominal diameter is used. The head loss across the heat exchanger is = 2388.7~, where Q [==] ft3 /s and I1H [ == J ft-lbf/lbm. The exit is 10 ft higher than the inlet. The heat exchanger is placed midway in the piping network and cools the water to 100°F.
(a) For a fully opened valve and Q = 160 gpm, determine the size of pump required (Q,head).
(b) If a Goulds 2 X 3-10 (A60) pump (Fig. 4-16) at 1,750 rpm is placed in the system, find
- The system/pump operating point.
- The pump placement required to avoid cavitation.
- The system/pump operating point if the valve is closed to the i-open position.