Experiment 5 - Series Parallel Centrifugal Pump

FACULTY : ENGINEERING TECHNOLOGY LABORATORY: HYDRAULICS AND HYDROLOGY EXPERIMENT: SERIES/PARALLEL CENTRIFUGAL PUMP

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FACULTY OF ENGINEERING TECHNOLOGY DEPARTMENT OF CIVIL ENGINEERING TECHNOLOGY

HYDRAULICS AND HYDROLOGY LABORATORY LABORATORY INSTRUCTION SHEETS COURSE CODE

BNP 20103

EXPERIMENT NO.

5

EXPERIMENT TITLE

SERIES/PARALLEL CENTRIFUGAL PUMP

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INTRODUCTION:

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PROCEDURE:

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RESULTS & CALCULATIONS

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ANALYSIS DISCUSSIONS: ADDITIONAL QUESTIONS: CONCLUSION:

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FACULTY : ENGINEERING TECHNOLOGY LABORATORY: HYDRAULICS AND HYDROLOGY EXPERIMENT: SERIES/PARALLEL CENTRIFUGAL PUMP

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STUDENT CODE OF ETHICS DEPARTMENT OF CIVIL ENGINEERING TECHNOLOGY

FACULTY OF ENGINEERING TECHNOLOGY

I hereby declare that I have prepared this report with my own efforts. I also admit to not accept or provide any assistance in preparing this report and anything that is in it is true.

1) Group Leader Name : Matrix No. :

__________________________________________(Signature) __________________________________ __________________________________

2) Group Member 1 Name : Matrix No :

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3) Group Member 2 Name : Matrix No. :

__________________________________________(Signature) __________________________________ __________________________________

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FACULTY : ENGINEERING TECHNOLOGY LABORATORY: HYDRAULICS AND HYDROLOGY EXPERIMENT: SERIES/PARALLEL CENTRIFUGAL PUMP

EDITION: REVISION NO: EFFECTIVE DATE: AMENDMENT DATE:

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1.0 OBJECTIVES a) To study the characteristics of single pump operation with variable flow rate and pump speeds. b) To investigate the effect of impeller style on pump performance. c) To study the characteristics of pump-in-series operation with variable flowrate and pump speeds. d) To study the characteristics of pump-in-parallel operation with variable flowrate and pump speeds. 2.0 LEARNING OUTCOMES At the end of this experiment students are able to: a) Demonstrate engineering flow systems confidently by using process fluid mechanics (C3, PLO2). b) Display macroscopic and microscopic momentum balances in laminar and turbulent flows including boundary layer flows effectively (P4, PLO4). c) Demonstrate the principles of process fluid mechanics in solving problems associated with process industries (A3, PLO6).

d) INTRODUCTION

3.1Pumps are used in almost all aspects of industry and engineering from feeds to reactors and distillation columns in chemical engineering to pumping storm water in civil and environmental. They are an integral part of engineering and an understanding of how they work is important. Centrifugal pump is one of the most widely used pumps for transferring liquids. This is for a number of reasons. Centrifugal pumps are very quiet in comparison to other pumps. They have a relatively low operating and maintenance costs. Centrifugal pumps take up little floor space and create a uniform and nonpulsating flow.

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3.2Centrifugal Pump Connected in Parallel: If a single pump does not provide enough flowrate for a given application, connecting two pumps in parallel, as shown in Figure 1, can rectify the problem. The effective two-pump performance curve is obtained by adding the flowrates of each pump at the same head. As shown, when two pumps are connected in parallel, the operating points shift from A to B, providing not only increased flowrate as required but also greater head. Figure 1 shows the characteristics of two identical pumps, but the pumps do not have to be the same.

Figure 1: Two centrifugal pumps connected in parallel

3.3

Centrifugal Pump Connected in Series: On the other hand, if a single

pump does not provide enough head for a given application, two pumps connected in series, as shown in Figure 2, can be a remedy. The effective twopump performance curve is obtained by adding the head of each pump at the same flowrate. The operating point shifts from A to B, thereby providing not only increased head as required but also greater flow. Figure 2 shows the characteristics of two identical pumps, but the pumps do not have to be the same.

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Figure 2: Two centrifugal pumps connected in series 4.0INSTRUMENTS /APPARATUS

Flow

Water

Pressure

Pressure

Pump, P2 Speed Pump, P1 Figure 3: Series/parallel pump (Model:FM07A)

5.0PROCEDURE Before conducting any experiment, it is necessary to do the following checking to avoid any misused and malfunction of equipment. 3

5.1 Single pump operation 1. The circulation tank is filled with water. 2. Make sure V5 (Figure 4) is in fully close position. 3. Switch on the main power supply. 4. Turn on the main switch on the control panel. Ensure all digital indicators illuminate. 5. Check for the following valve position as shown in Table 1. Table 1: Valve and pump position for single operation Fully close Valve V2 & V3

Fully open valve V1 & V4

Running pump Pump 1, P1

6. Turn the pump speed controller clockwise until maximum and turn on the pump. Slowly open V5 until maximum flowrate is achieved (follow the desired flowrate in data sheet). 7. Record the pump speed (use the pump speed selector switch to monitor the pump speed), power, and pressure (Use the pressure selector switch to monitor the pressure in the pipe). 8. Repeat step 6 and 7 with other condition: maximum V5 and vary motor speed (follow the desired motor speed in your data sheet). 9. Regulate the pump speed controller (fully anti-clockwise) to stop the pump speed. 10.Turn off the pump. Make sure valve V5 is in fully close position. Turn off the main switch on the control panel and switch off the main power supply.

5.2 Series pump operation 1. Repeat step 1 to 4 in procedure 5.1 above. 2. Check for the following valve position as shown in Table 2. Table 2: Valve and pump position for series operation Fully close Valve V2 & V4

Fully open valve V1 & V3

Running pump Both pump, P1 & P2

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3.

Follow the same step from 6 to 10 in procedure 5.1 to determine the characteristics of pump in series operation with variable flowrate and pump speeds.

5.3 Parallel pump operation 4. Repeat step 1 to 4 in procedure 5.1 above. 5. Check for the following valve position as shown in Table 3. Table 3: Valve and pump position for parallel operation Fully close Valve V3

Fully open valve V1, V2 & V4

Running pump Both pump, P1 & P2

6. Follow the same step from 6 to 10 in procedure 5.1 to determine the characteristics of pump in parallel operation with variable flowrate and pump speeds.

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Figure 4: Process diagram for series/parallel pump

6.1RESULTS & CALCULATIONS 6.2 Results

Table 6.1: Single pump operation with variable flowrate

Flowrate

Speed

Power

(LPM)

(RPM)

(Watt)

Pressure

Pressure

PT1

PT3

(bar)

(bar)

Pressure PT3 – PT1 (bar)

Pump head, H (m)

Efficiency (%)

40 50 60 70 80

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Table 6.2: Single pump operation with variable pump speed Speed

Flowrate

Power

(RPM)

(LPM)

(Watt)

Pressure

Pressure

PT1

PT3

(bar)

(bar)

Pressure PT3 – PT1 (bar)

Pump head, H (m)

600 1000 1400 1800 2200

Table 6.3: Series pump operation with variable flow rate Average Flowrate

speed,

Power

(LPM)

P1 & P2

(Watt)

Pressure

Pressure

Average

Pressure

PT1

PT2

PT1 &

PT3

(bar)

(bar)

PT2

(bar)

(RPM)

Pressure PT3 – PT1 (bar)

Pump head,

Efficiency (%)

H (m)

40 50 60 70 80

Table 6.4: Series pump operation with variable pump speeds

Speed

Flowrate

Power

(RPM)

(LPM)

(Watt)

Pressure

Pressure

PT1

PT3

(bar)

(bar)

Pressure PT3 – PT1 (bar)

Pump head, H (m)

600 1000 1400 1800 2200

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Table 6.4: Series pump operation with variable flow rate Average Flowrate

speed,

Power

(LPM)

P1 & P2

(Watt)

Pressure

Pressure

Average

Pressure

PT1

PT2

PT1 &

PT3

(bar)

(bar)

PT2

(bar)

(RPM)

Pressure PT3 – PT1 (bar)

Pump head,

Efficiency (%)

H (m)

40 60 80 100 120 140

Table 6.6: Parallel pump operation with variable pump speeds

Speed

Flowrate

Power

(RPM)

(LPM)

(Watt)

Pressure

Pressure

PT1

PT3

(bar)

(bar)

Pressure PT3 – PT1 (bar)

Pump head, H (m)

600 1000 1400 1800 2200

6.3 Calculations a) Table 4 is especially important to convert the pressure readings on the panel into bar (g). Table 4: Range and total range of pressure transmitter Pressure Transmitter Pressure Transmitter (PT1)

Range, bar -1 to 1.5 bar

Total range, bar 2.5 8

Pressure Transmitter 2 (PT3) Pressure Transmitter 3 (PT3)

-1 to 3 bar 0 to 6 bar

4 6

pressure on panel, x total range , ¯¿ 100 ¿ Pressure, ¯¿ ¿

b) Overall efficiency;

Π overall =

POWER fluid x 100 POWER electrical

c) Power (fluid);

Pfluid =g . Q . H . ρwater d) Volumetric flow rate;

s m3 /¿ ¿ Q¿

e) Pump head, H

H ( m) =

PT 3−PT 1 ρg

*Pressure (PT3-PT1) unit is pacsal and unit conversion; 1 bar = 100,000 Pascal. f)

Water density, ρwater = 1,000 kg/m3 and gravitational acceleration, g = 9.81 m/s2

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7.0ANALYSIS Please analyze the data and results obtained in this experiment. Include the condition of graft as below in your analysis; 1) Plot pressure difference pump head (m) vs. flowrate for variable flow rate (single, series and parallel operation). 2. Plot efficiency vs. flow rate for variable flow rate (single, series and parallel operation). 3. Plot flow rate vs. pump speed for variable pump speed (single, series and parallel operation). 4. Plot pump head vs. pump speed for variable flow rate (single, series and parallel operation).

8.0DISCUSIONS Discuss your results both on the basis of any theory presented and on their relevance to practical applications and current industrial practice. Compare the pump performance between single, series and parallel pump operation.

9.0 ADDITIONAL QUESTIONS 1. Why you should use circulating pumps in parallel & series centrifugal pumping? 2. Describe the performance of a pump?

3. A centrifugal pump has a 100 mm diameter suction pipe and a 75 mm diameter delivery pipe. When discharging 15 l/s of water, the inlet water mercury manometer with one limb exposed to the atmosphere recorded a vacuum deflection of 198 mm; the mercury level on the suction side was 100 mm below the pipe centerline. The delivery pressure gauge, 200 mm above 10

the pump inlet, recorded a pressure of 0.95 bar. The measured in

put power

was 3.2 kW. Calculate the pump efficiency. (See Fig.5).

Figure 5

4. Two identical pumps having the tabulated characteristics are to be installed in a pumping station to deliver sewage to a settling tank through a 200 mm uPVC pipeline 2.5 km long. The static lift is 15 m. Allowing for minor head losses of 10.0V2/2g and assuming an effective roughness of 0.15 mm calculate the discharge and power consumption if the pumps were to be connected: (a) in parallel, and (b) in series. Pump Characteristics discharge (l/s)

0

10

20

30

40

Total head (m)

30

27.5

23.5

17

7.5

44

58

50

18

Overall efficiency (per cent)

10.0

CONCLUSION

Conclusion is merely a summary, presented in a logical order, of the important findings already reported in the discussion section. It also relates to the objectives. 11

Prepared by/Disediakanoleh :

Approved by/Disahkanoleh :

Signature/Tandatangan : Name/Nama : DR. NOR HASLINA HASHIM

Signature/Tandatangan : Name/Nama : PROF. MADYA DR. ISHAK BABA

Date/Tarikh : AUGUST 2016

Date/ Tarikh : AUGUST 2016

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