The flow system as shown in the Figure, the centrifugal pump(3500 R.P.M.) is delivering water at 100 gal/min and 70 °F into a boiler operating at a pressure of 35 psig. The water levels in the feed tank and boiler are constant. Because corrosion is expected to be negligible, select the suitable material to be used for this purpose. Assume frictional pressure drop of 5 psi across the heat exchanger. The following data are available:
Note:
(a) For NPSH required:
Total Head (ft.) 15 18 20 25 30 40
Flow rate, (gal/min) 25 30 85 105 120 155
(b) Use the physical properties of water from textbooks.
Find:
1. The suction and discharge pipe sizes
2. The head the pump must deliver
3. The break horsepower
4. The electric-motor horsepower
5. Draw the required curves
6. If cavitation will occur in the pump
7. Complete the following summary Tables (one variables and another for fittings):
Variable Suction Discharge
Flow rate (gal/min)
Density, (lb/ft3)
Pipe ID (ft)
Pipe Length, (ft)
Velocity (ft/s)
Viscosity (lb/ft.s)
Reynolds Number
Relative Roughness
Friction Factor, 4f