West Virginia University

MAE 331 Fluid Mechanics Spring 2015

Design Project

It is desired to design a pump-piping system to keep a 1-million-gallon capacity water tank filled. The plan

is to use a modified (in size and speed) version of the model 1206 centrifugal pump manufactured by Taco

Inc., Cranston, Rhode Island. Test data have been provided to us by Taco Inc. for a small model of this

pump: 5.45 in.D , 1760 rpm , tested with water at 20 C:

Q, gal/min 0 5 10 15 20 25 30 35 40 45 50 55 60

H, ft 28 28 29 29 28 28 27 26 25 23 21 18 15

Efficiency, % 0 13 25 35 44 48 51 53 54 55 53 50 45

The tank is to be filled daily with rather chilly (10 C) groundwater from an aquifer, which is 0.8 miles

from the tank and 150 ft lower than the tank. Estimated daily water use is 1.5 million gal/day. Filling time

should not exceed 8 h/day. The piping system should have four gate valves with variable openings, 10

elbows of various angles, and galvanized iron pipe of a size to be selected in the design. The design should

be economicalboth in capital costs and operating expense. Taco Inc. has provided the following cost estimates for system components:

Pump and motor $3500 plus $1500 per inch of impeller size

Pump speed Between 900 and 1800 rpm

Valves $300 plus $200 per inch of pipe size

Elbows $50 plus $50 per inch of pipe size

Pipes $1 per inch of diameter per foot of length

Electricity cost 10 per kilowatt-hour

Your design task is to select an economical pipe size and pump impeller size and speed for this task, using

the pump test data in nondimensional form as design data. Write a brief technical report (five to six

printed pages) showing a schematic diagram of the pump-piping system design, the calculations and

graphs, and the references used.