Problem 3. Performance data for a pump are given in the table below. From a curve fit to the data, the pump curve is given by H, = H, – C, Q² whereHo = 180 ft and C, = 1.524 × 10-6 ft/gpm?. This pump is used to move water at STP between two open reservoirs with an elevation increase of Az = 50 ft through a commercial steel pipe of length L = 1200 ft and diameter D = 1.0 ft that contains two 90° elbows (equivalent length of 30 diameters) and an open gate valve (equivalent length of 8 diameters). The flow entrance and exit for the reservoirs are abrupt. (a) Plot the pump curve and system curve on the same figure. (b) Calculate the flowrate with the gate valve open. (c) Calculate the equivalent length for the gate valve in order to reduce the flowrate by half. NOTE: Your calculations for this problem will require iteration because the friction factor for this case does depend on Q. Thus, it is recommended you use either EES (see solution for Example 19 from lecture) or Excel to get converged values. Q (gpm) Н, (ft) 500 1000 1500 2000 2500 3000 179 176 165 145 119 84 43

Problem 3. Performance data for a pump are given in the table below. From a curve fit to the data, the pump curve is given by H, = H, – C, Q² whereHo = 180 ft and C, = 1.524 × 10-6 ft/gpm?. This pump is used to move water at STP between two open reservoirs with an elevation increase of Az = 50 ft through a commercial steel pipe of length L = 1200 ft and diameter D = 1.0 ft that contains two 90° elbows (equivalent length of 30 diameters) and an open gate valve (equivalent length of 8 diameters). The flow entrance and exit for the reservoirs are abrupt. (a) Plot the pump curve and system curve on the same figure. (b) Calculate the flowrate with the gate valve open. (c) Calculate the equivalent length for the gate valve in order to reduce the flowrate by half. NOTE: Your calculations for this problem will require iteration because the friction factor for this case does depend on Q. Thus, it is recommended you use either EES (see solution for Example 19 from lecture) or Excel to get converged values. Q (gpm) Н, (ft) 500 1000 1500 2000 2500 3000 179 176 165 145 119 84 43

Elements Of Electromagnetics

7th Edition

ISBN:9780190698614

Author:Sadiku, Matthew N. O.

Publisher:Sadiku, Matthew N. O.

ChapterMA: Math Assessment

Section: Chapter Questions

Problem 1.1MA

See similar textbooks

Similar questions

A manufacturer of small water pumps lists the performance data for a family of its pumps as a parabolic curve fit, Havailable = H0 − aV.2 , where H0 is the pump’s shutoff head and a is a coefficient. Both H0 and a are listed in a table for the pump family, along with the pump’s free delivery. The pump head is given in units of feet of water column, and capacity is given in units of gallons per minute. (a) What are the units of coefficient a? (b) Generate an expression for the pump’s ree delivery V.max in terms of H0 and a. (c) Suppose one of the manufacturer’s pumps is used to pump water from one large reservoir to another at a igher elevation. The free surfaces of both reservoirs are exposed to atmospheric pressure. The system curve simplifies to Hrequired = (z2 − z1) + bV.2 Calculate the operating point of the pump (V. operating and Hoperating) in terms of H0, a, b, and elevation difference z2 − z1.
a pump operating at 1750 rpm delivering 600 gpm against total head of 200 tt. changes in the piping system have increase the total head of 450 tt. At what RPM should the pump be operated to achieve thus new head at the same efficiency?
The MITL ME laboratory has installed a double-suction, three-stage, centrifugalpump with a discharge of 330 gpm under 200 ft head and running at 1200 rpm. It isproposed to install another pump with double suction and six stages, but of the samecharacteristics, to operate at 98 ft head and deliver 430 gpm. Calculate a) the speed ofthe proposed pump; b) the impeller diameter of the proposed pump if the diameter of theexisting pump is 6 inches; and c) the type of the existing and the proposed pump.
The plunger diameter of a single acting reciprocating pump is 115 mm and the stroke is 230 mm. The suction pipe is 90 mm in diameter and 4.2 m long. If cavitation takes place at the suction head of 4 m, the barometer stands at 10,3 m of water, and the water level in the sump is 3 m below the pump cylinder axis. 2.1 Find the maximum allowable speed to operate the pump 2.2 What power is expected in overcoming friction at this speed, take f=0.01
For each statement, choose whether the statement is true or false, and discuss your answer briefly: (a) If the rpm of a pump is doubled, all else staying the same, the capacity of the pump goes up by a factor of about 2. (b) If the rpm of a pump is doubled, all else staying the same, the net head of the pump goes up by a factor of about 2. (c) If the rpm of a pump is doubled, all else staying the same, the required shaft power goes up by a factor of about 4. (d) If the rpm of a turbine is doubled, all else staying the same, the output shaft power of the turbine goes up by a factor of about 8.
A radial flow pump operating at maximum efficiency at a specific speed of 2300 is to deliver 260gpm against a head of 129ft at a rotative speed of 2100 rpm. Find the required number of stages. ANSWER: 3
A centrifugal pump impeller delivers 4000 gal/min ofwater at 20 ° C with a shaft rotation rate of 1750 r/min.Neglect losses. If r 1 =6 in, r 2 = 14 in, b 1 = b 2 =1.75 in,V t 1 = 10 ft/s, and V t 2 = 110 ft/s, compute the absolutevelocities ( a ) V 1 and ( b ) V 2 and ( c ) the horsepower required.( d ) Compare with the ideal horsepower required.
A volute centrifugal pump with an impeller diameter of 0.02 m has the following performance data when pumping water at the best efficiency point: impeller speed N = 58.3 revs/s capacity Q = 0.012 m3/s total head Ah = 70m required net positive suction head NPSH = 18m brake power Pe = 12000w Determine the new performance data (listed above) of a homologous pump with twice the impeller diameter operating at half the impeller speedand same efficiency.
The turbine of a micro-hydroelectric power plant delivers 65hp at 75% efficiency. If the effective head is 115ft, how many cubic feet per minute of water must be used.
For a centrifugal pump of impeller diameter D rotating at N to develop a head of H and discharge Q, what would be the new head developed by the same pump if we halve the impeller speed to N/2? H/A 2H H 4H H/2
Pumps: A centrifugal pump having 4 stages in parallel, delivers 18 kiloliters/min of liquid against a head of 25 m. The diameter of the impellers being 24 cm and the speed of 1800 rpm. A pump is to be made up with a number of stages in series of similar construction to that of the first pump to run at 1250 rpm and to deliver 15 kiloliters/min against a totalhead of 250 m. Find the diameter of the impellers and the number of stages required in this case. Answer: D = 46.63 cm, n = 6 stages
A plant has installed a single suction centrifugal pump with a discharge of 68 m3/hr under 60 m head and running at 1200 rpm. It is proposed to install another pump with double suction but of the same type to operate at 36.27 m head and deliver 90 m3/hr. Determine the speed of the new pump. What should be the new impeller diameter if the diameter of the original pump is 140mm?