i

Fluid Mechanics and Hydraulic

Machinery

LAB MANUAL

ST. MARTIN’S ENGINEERING COLLEGE

DHULAPALLY, KOMPALLY, SECUNDERABAD-500014

ii

Department of Civil Engineering

FLUID MECHANICS AND

HYDRAULIC MACHINERY

LAB

I SEMESTER – CE

Department of Civil Engineering

St.MARTIN’S ENGINEERING COLLEGE, SECUNDERABAD-14

iii

Vision

To establish a center of excellence for providing high quality education in

civil engineering to produce professionals with innovative technical skills to

meet global challenges

Mission

M1: Impart conceptual and practical education to the students to achieve

their goals along with ethical and social values in consistence with

institutional mission.

M2: Adopt policies to enhance research oriented activities for the

students by collaborating with government, public and private sector

units.

M3: Conduct technical activities and personality development for

education beyond curriculum so that the students emerge as

entrepreneurs, professionals, scientists and bureaucrats.

iv

S.No. Program Educational Objectives

PEO1

Impart fundamental education to students in civil engineering core

& allied subjects to develop them as full-fledged civil engineers

through strong communication and entrepreneurial skills for the

society.

PEO2

To train the students so that they can work and contribute to the

infrastructure development projects being undertaken by

Government, public sector and private sector companies.

PEO3

Continue their education programs in engineering &

interdisciplinary areas to emerge as researchers, experts, educators

& entrepreneurs for professional development and life-long

learning.

v

Program Specific Outcomes

PSO1 An ability of a graduate to use their knowledge in the analysis

and design of civil infrastructure projects in subjects like structural, transportation, soil, environmental and water

resources engineering etc

PSO2 An ability of a graduate to execute the projects with the knowledge of managerial principles and financial implication in

subjects like Construction management, Estimation and Costing, Survey, MEFA etc

PSO3 An ability of a graduate to Amalgate technical, co-curricular and soft skills training to face and succeed in competitive

examinations like GATE, GRE, TOFEL, GMAT etc.

vi

Program Outcomes

PO1 Engineering knowledge: Apply the knowledge of mathematics, science,

engineering fundamentals, and an engineering specialization to the solution of

complex engineering problems.

PO2 Problem analysis: Identify, formulate, review research literature and analyze

complex engineering problems reaching substantiated conclusions using first

principles of mathematics, natural sciences and engineering.

PO3 Design/development of solutions: Design solutions for complex

engineering problems and design system components or processes that meet

the specific needs with appropriate consideration for the public health and

safety and the cultural, social and environmental considerations.

PO4 Conduct investigations of complex problems: Use research- based

knowledge and research methods including design of experiments, analysis

and interpretation of data and synthesis of the information to provide valid

conclusions.

PO5 Modern tool usage: Create, select and apply appropriate techniques,

resources and modern engineering and IT tools including prediction and

modeling to complex engineering activities with an understanding of the

limitations.

PO6 The Engineer and the society: Apply reasoning informed by the contextual

knowledge to assess societal, health, safety, legal and cultural issues and the

consequent responsibilities relevant to the professional engineering practice.

PO7 Environment and sustainability: Understand the impact of the professional

engineering solutions in societal and environmental contexts, and

demonstrate the knowledge of, and need for sustainable development.

PO8 Ethics: Apply ethical principles and commit to professional ethics and

responsibilities and norms of the engineering practice.

PO9 Individual and team work: Function effectively as an individual, as a

member or a leader in diverse teams, and in multidisciplinary settings.

PO10 Communication: Communicate effectively on complex engineering activities

with the engineering community and with society at large, such as, being able

to comprehend and write effective reports and design documentation, make

effective presentations, and give and receive clear instructions.

PO11 Project management and finance: Demonstrate knowledge and

understanding the engineering and management principles and apply these to

one’s own work, as a member and leader in a team, to manage projects and in

multidisciplinary environments.

PO12 Life-long learning: Recognize the need for, and have the preparation and

ability to engage in independent and life-long learning in the broadest context

of technological change.

vii

Do’s

1 Do maintain punctuality to the laboratory timings

2 Do keep the bags and belongings in the allotted place

3 Do wear shoes and aprons strictly

4 Do listen and follow the instructions and guidelines of the faculty only

5 Do maintain silence in the laboratory

6 Do bring the laboratory observation book for every laboratory session

7 Do get the observation book signed before leaving the laboratory

8 Do keep the laboratory record book up to date

9 Do maintain the laboratory neat, clean and tidy

Don’ts

1 Do not touch the equipments unless instructed by lab in-charge.

2 Do not operate the equipments unless instructed by lab in-charge.

3 Do not damage the equipments.

4 Do not interfere with others experiments.

5 Do not interact with the students other than batch-mates.

6 Do not leave the laboratory without switching off the equipments.

7 Do not leave the laboratory without the permission of laboratory in-charge.

8 Do not throw the papers and material on the floor, use dustbin.

viii

FLUID MECHANICS AND HYDRAULIC

MACHINERY LAB

INDEX

LIST OF EXPERIMENTS

Page No

1 Calibration of Venturimeter & Orifice meter 1 - 8

2 Determination of Coefficient of discharge for a small orifice / mouthpiece

by constant head method. 9 - 13

3 Calibration of contracted Rectangular Notch and / Triangular Notch 14 - 18

4 Determination of friction factor of a pipe. 19 - 22

5 Determination of Coefficient for minor losses. 23 - 26

6 Verification of Bernoulli’s equation. 27 - 30

7 Impact of jet on vanes 31 - 34

8 Study of Hydraulic jump. 35 - 38

9 Performance test on Pelton wheel turbine 39 - 43

10 Performance test on Francis turbine. 44 - 47

11 Performance characteristics of a single stage / multi-stage centrifugal

pump. 48 - 55

12 Performance characteristics of a reciprocating pump. 56 - 58

TESTS BEYOND SYLLABUS COVERAGE

1 Performance test on kaplan turbine 60 - 64

ix

ATTAINMENT OF PROGRAME OUTCOMES

S. No LABORATORY TASKS PERFORMED

Program

Outcomes

attained

1 Calibration of Venturimeter & Orifice meter

PO1, PO2, , PO6,

PO9, PO11, PO12,

PSO1, PSO2

2 Determination of Coefficient of discharge for a small

orifice / mouthpiece by constant head method.

PO1, PO2, , PO6,

PO9, PO11, PO12,

PSO1, PSO2

3 Calibration of contracted Rectangular Notch and /

Triangular Notch

PO1, PO4, PO9,

PO11, PO12, PSO1,

PSO2

4 Determination of friction factor of a pipe.

PO1, PO2, PO4,

PO9, PO11, PO12,

PSO1, PSO2

5 Determination of Coefficient for minor losses.

PO1, PO2, PO4,

PO9, PO11, PO12,

PSO1, PSO2

6 Verification of Bernoulli’s equation.

PO1, PO3, PO4,

PO5, PO9, PO11,

PO12, PSO1, PSO2

7 Impact of jet on vanes

PO1, PO4, PO9,

PO11, PO12, PSO1,

PSO2

8 Study of Hydraulic jump.

PO1, PO4, PO9,

PO11, PO12, PSO1,

PSO2

9 Performance test on Pelton wheel turbine

PO1, PO2, PO4,

PO5, PO9, PO11,

PO12, PSO1, PSO2

10 Performance test on Francis turbine.

PO1, PO3, PO4,

PO5, PO9, PO11,

PO12, PSO1, PSO2

11 Performance characteristics of a single stage / multi-

stage centrifugal pump.

PO1, PO3, PO4,

PO5, PO9, PO11,

PO12, PSO1, PSO2

12 Performance characteristics of a reciprocating pump.

PO1, PO3, PO4,

PO5, PO9, PO11,

PO12, PSO1, PSO2

x

FLUID MECHANICS AND HYDRAULIC MACHINERY LAB

OBJECTIVE: .

The objective of this lab is to teach students, the knowledge of various flow meters and the concept of fluid

mechanics. This lab helps to gain knowledge on working of centrifugal pumps, positive displacement

pumps, and hydraulic turbines. Students will compare the performance of various machines at different

operating points.

OUTCOMES:

Understand the working of different fluid and hydraulic machines

Examine the flow through orifice mouth piece.

Analyze the flow through rectangular and V-notch.

Understand the concept of pipe flow losses.

Understand the Impact of jet on vanes.

Verify the Bernoulli’s theorem

Determine the flow parameters in hydraulic jump

Examine the Francis and Pelton wheel turbine.

Examine the centrifugal and reciprocating pumps.

1

EXPERIMENT NO-1(a): CALIBRATION OF VENTURIMETER

1.1 OBJECTIVE:- To determine the coefficient of discharge of the given flow meter.

1.2 RESOURCES:-Venturimeter experimental setup, stop watch.

1.3 THEORY: A flow meter is used to measure the flow rate of a fluid in a pipe. A

venturimeter consist of short length of a pipe narrowing to a throat in the middle and

then diverging gradually to the original diameter of the pipe. As the water flow through

these meters, velocity is increased due to the reduced area and hence there is a pressure

drop.

A venturimeter is a device which is used for measuring the rate of flow of fluid through

the pipe.

1.4 PRINCIPLE:-The basic principle on which a venturimeter works is that by reducing

the cross sectional area of the flow passage, a pressure difference created and the

measurement of the pressure difference enables the determination of the discharge

through the pipe.

Venturimeter consist of 1. An inlet section which is in the form of convergent cone 2.

Throat 3.outlet section which is in the form of divergent cone. The inlet section of the

venturimeter is of the same diameter as that of the pipe diameter. The convergent cone

is a short pipe which tapers from the original size of the pipe so that the throat of the

venturimeter. The throat is a short pipe having its cross sectional area smaller than that

of the pipe .The divergent cone of the venturimeter is a gradually diverging pipe with its

cross section area increasing from that of throat i.e 1 and 2 of the venturimeter

Pressure taps are provided through the pressure ring as shown in the figure.

The length of convergent cone is equal to the (D-d).where ‘D’ is the diameter of the inlet

section and ‘d’ diameter of throat .The length of the pipe is equal to the diameter of the

pipe. The diameter of the throat may vary from 1/3 to ¾ of the pipe diameter.

The divergent cone has more length as that of the convergent cone due to avoid the

possibility of flow separation (eddies) and energy loss.

The cross section area of the throat is smaller than the cross section area of the inlet

section .According to the continuity equation the velocity of the flow at the throat will

become greater than that at inlet section .The increase in the velocity of the flow at the

throat result in the decrease in the pressure .so the pressure difference will be developed

between the inlet and the throat .This pressure difference can be determined by using

suitable manometer.

1.5 EXPERIMENTAL PROCEDURE:

1. Select the required flow meter.

2. Open its pressure valves and close the other pressure valves, so that only pressure for

the flow meter in use is communicated to the manometer.

3. Open the flow control valve and allow a certain flow rate.

4. Observe the reading of the manometer. And change the flow rate.

5. Note down the readings of the manometer.

2

6. Collect the water in the collecting tank .Close the drain valve and find the time taken

for 5cm rise in the tank.

Schematic diagram of venturimeter:

Venturimeter

1.6 CALCULATIONS:

h1= manometric head in the left limb.

h2= manometric head in the right limb.

t=time taken for hcm rise of water in tank.

Manometeric head h=( h2- h1)x 𝑖 𝑖 𝑎 𝑖 𝑦 𝑙𝑖 𝑖 𝑎 𝑖 𝑦 𝑎 -1

Specific gravity of ccl4=1.6.

Specific gravity of water=1.

3

Theoretical discharge Q t =k x√ ℎ m3/s.

k= a a √a − a

Where a1=area of cross section of pipe.

a2=area of cross section of the throat. 𝑄 𝑎=volume of the water collected in the tank i.e. [area of the tank x rise of water level

in the tank] m3/s.

Coefficient of discharge (Cd)= a t

1.7 TABULAR COLUMN:

S.N

o

Manometeric

reading

Time taken for h

cm

rise of water in

tank (s)

Theoretica

l

discharge

Qt m3/sec

Actual

discharg

e Qa

m3/sec

Coefficient

of discharge

(Cd) 1 h1(cm) h2(cm)

2

3

4

5

1.8 GRAPH:

1. Cd versus Qa

2. Cd versus Qt

1.9 RESULT: The coefficient of discharge of venturimeter is Cd=

1.10 : PRE-LAB QUESTIONS:

1. What are the applications of Bernoulli’s equation?

A. Venturi meter, Orifice meter, Pitot tube, Nozzle meter

2. What is Venturi meter? And what is its use?

A. Venturi meter is a device which is used for measuring the rate of

flow of fluid through a pipe

3. Who demonstrated the principle of Venturi meter first?

A. The Principle of Venturi meter was first demonstrated in 1797 by Italian

Physicist

G.B. Venturi (1746 - 1822).

4. Who applied Venturi meter principle?

4

A. C. Herschel (1842-1930) applied Venturi meter principle in 1887.

5. What is the basic principle of venturi meter?

The basic principle on which a venturi meter works is that by reducing the

cross- sectional area of the flow passage, a pressure difference is created and

the measurement of the pressure difference enables the determination of the

discharge through the pipe.

1.11 : POST-LAB QUESTIONS:

6. What are the parts of Venturi meter?

A. a. An inlet section followed by a convergent cone

b. A Cylindrical throat

c. A gradually divergent cone

7. What is convergent cone?

A. It is a short pipe which tapers from the original size of the pipe to

that of the throat of the venturi meter

8. What is throat of Venturi meter?

A. The throat of the Venturi meter is a short parallel sided tube

having its cross- sectional area smaller than that of the pipe.

9. What is divergent cone?

A. It is a gradually diverging pipe with its cross-sectional area increasing

from that of the throat to the original size of the pipe.

10. Where pressure taps are provided?

A. At the inlet section and throat.

5

EXPERIMENT-1(b): CALIBRATION OF AN ORIFICEMETER

1b.1 OBJECTIVE: To determine the coefficient of discharge of the given flow meter.

1b.2 RESOURCES: orifice meter experimental setup, stopwatch.

1b.3 THEORY: An orifice meter is another simple device used for measuring the

discharge through a pipe. Orifice meter also works on the same principle as that of

venturimeter i.e. by reducing the cross sectional area of the flow passage a pressure

difference between the two sections is developed and the measurement of the pressure

difference enables the determination of the discharge through the pipe.An orifice meter is

a cheaper arrangement for discharge measurement through pipes and it’s installation

requires a smaller length, as compared with venturimeter. As such where the space is

limited, the orifice meter may be used for discharge of through pipes.

An orifice meter consists of a flat circular plate with circular perforated hole called orifice

which is concentric with the pipe axis. The thickness of the plate is less than an equal to

0.05 times the diameter of the pipe. The diameter of the orifice may vary from 0.2 to

0.85 times the pipe diameter but generally the diameter is kept as 0.5 times pipe

diameter.

Two pressure taps are provided at section-1 on the upstream side of the orifice plate and

other at section-2 on the downstream side of the orifice plate since in the case of an

orifice change in the cross section as area of the flow passage is provided and there

being a gradual change in the cross sectional area of the flow passage as in the case of

venturimeter there is a gradual loss of energy in a orifice meter than in a venturimeter.

The experimental setup consist of 200mm pipe lines fixed to an MS stand .The pipe is

connected with an orifice meter with the action valves for pressure tapping’s. The meter

is connected to a common middle chamber, which is in turn connected to a mercury

chamber. The pipe line is provided with a flow control valve.

1b.4 Experimental Procedure:

1. Select the required flow meter.

2. Open its pressure valves and close the other pressure valves so that only pressure for

the meter in use is communicated to the manometer.

3. Open the flow control valve and allow certain a flow rate.

4. Observe the reading in the manometer.

5. Collect the water in the collecting tank .close the drain valve and find the time taken

for 5cm rise in the tank.

6

Schematic diagram of Orificemeter

1b.5 CALCULATIONS:

Theoretical discharge(Qt)

h1= manometric head in the left limb.cm

h2= manometric head in the right limb.cm

Difference in the manometer level =h=h1-h2 cm

t=time taken for hcm rise of water in tank.

Theoretical discharge Qt=K√ℎ

k= a a √a − a

a1= area of cross section of the pipe.

a2=area of the throat.

Actual discharge (Qa)

The area of the collecting tank =50cm*50 cm

Rise of water level in the tank =5cm

Time taken for collecting ‘ h ‘in the collecting tank

Qa=AR/t

Coefficient of discharge Cd=Qa/Qt

7

1b.6TABULAR COLUMN OF ORIFICE-METER:

S.NO

Manometer Reading

H=x( -

1)

Time

taken (t

sec) for

5cm rise

water

Qt= K√ℎ

(cm3/se

c)

Qa=AR/

t

Cm3/se

c

Coefficient

discharge of

orifice-meter

(Cd)

h1(Cm) h2(cm) H=h2-

h1(cm)

1

2

3

4

1b.7 GRAPHS:

1. Actual discharge versus Theoretical discharge.

2. Actual discharge versus Coefficient of discharge.

1b.8 RESULT: The coefficient of discharge (Cd) for orificemeter is _______________

1b.9 : PRE-LAB QUESTIONS:

1. What is the length of the convergent

cone?

2.7 (D-d) D = Diameter of the inlet

section d = Diameter of the

throat

2. What is the included angle of divergent cone?

50 to 150 (preferably about 60)

3. Which part is smaller, convergent cone or divergent cone? Why?

Convergent cone is smaller. To avoid the possibility of flow separation

and the consequent energy loss, the divergent cone of the venturi

meter is made longer with a gradual divergence.

4. Where separation of flow occurs?

In Divergent cone of Venturi meter

5. Which portion is not used for discharge measurement?

Divergent cone

8

1b.10 : POST-LAB QUESTIONS:

6. How pressure difference is determined?

By connecting a differential manometer

7. Between which sections the pressure difference can be determined?

Inlet section and Throat

8. What we should do for getting greater accuracy in the measurement of

the pressure difference?

The cross sectional area of the throat should be reduced so that the

pressure at throat is very much reduced.

9. What is cavitation?

The formation of the vapour and air pockets in the liquid ultimately

results in a phenomenon called Cavitation.

10. What is value of diameter of throat?

The diameter of throat may very from 1/3 to ¾ of the pipe diameter

9

EXPERIMENT.2 MOUTH PIECE EXPERIMENTAL SET UP

2.1 OBJECTIVE: To determine the co-efficient of discharge (Cd) for a given Mouth

Piece.

2.2 RESOURCES:

1) Header tank with provisions to fix mouth pieces

2) A vertical level gauge (Piezometer) fitted with the tank to record the water level in

the tank.

3) A constant and steady supply of water with a means of varying the flow rate by

using mono block centrifugal pump and control valve.

2.3 THEORY:

A mouth piece is a short tube of length not more than two or three times

its diameter, which is fitted to a circular opening or orifice of the same diameter.

Mouth pieces are usually used for measuring the rate of flow of fluid.

Mouth pieces may be classified on the basis of their shape, position and the

discharge conditions according to the shape the mouth pieces may be classified as

cylindrical, convergent, divergent and convergent-.divergent. According to the

position the mouth pieces may be classified as external and internal Mouth piece.

An external mouth piece is the one which is fitted to tank or reservoir and it may

be of any of the shapes noted above. An internal mouth piece is also called

reentrant or Borda’s mouthpiece which is fitted to a tank or a reservoir such that it

is projecting inside the tank and it is generally of cylindrical shape only. According

to the discharge conditions the mouthpieces may be classified as running full or

running free mouth pieces. Generally these conditions of discharge may be

developed only in the case of internal mouthpieces.

Values of Co-efficients:

a) Flow through an external cylindrical mouth piece – Cd value is 0.82

b) Flow through convergent & divergent mouthpiece - Cd value is 0.975

c) Flow through internal or Re– entrant or Borda’s mouthpiece – Cd – 0.5

The coefficient of discharge of mouthpieces is greater than orifice as per theory.

Formulae

1. Theoretical Discharge, Qth

Theretical Velocity

Qth =

Area of Jet

10

Qth a = m3/sec

Where,

h= Head over the mouthpiece = m

d 2

a = Area of jet = 4 = m2

2. Actual Discharge, Qact

Ac x r

Qact = t

m

3/sec

where

,

Ac = Area of collecting tank = 0.3 m x 0.5 m m

2

r = rise of water level m

t = time taken for r rise of water sec

3. Co-efficient of Discharge, Cd

Actual Disch arg e

Qact

Cd =

Theoritical Disch arg e =

Qth

2gh

11

2.4 PROCEDURE:

1) Note the dimensions of the discharge measuring tank.Check that the zero of

the scale of the inlet tank is the same level as the center line of the

mouthpiece or orifice. If not, measure the difference in elevation and take it

as zero error.

2) Adjust the opening of the inlet valve till the water level in the supply tank

become steady.

3) Note down the head.

4) Using the hook gauge arrangement measure the co-ordinates of the jet in a

convenient point.

5) Using collecting tank and stop watch setup measure the actual discharge.

6) Repeat the experiment for different inlet valve openings and tabulate the

readings.

2.5 OBSERVATIONS:

Ac= Area of collecting tank = m2

d = Diameter of the Mouth Piece= 36x10-3 m

2.6 TABLE OF READINGS:

Type of

Mouthpiece

Diameter

of Mouth

Piece

Head over

the

Mouthpiece

‘h’

Water

collected

in

collecting

tank ‘r’

Time taken

for ‘r’ rise

‘t’

Units mm m cm m cm m Sec

2.7 TABLE OF CALCULATIONS:

Actual

Discharg

e (Qact)

Theoretic

al

Discharg

e (Qth)

Coefficient

of Discharge

(Cd)

m3/sec m3/sec

2.8 GRAPHS:

A graph between Qact and √H is drawn.

2.9 RESULTS:

Co-efficient of Discharge for the given Mouth Piece from Experiment =

2.10 PRE-LAB QUESTIONS

1. . For which one, the coefficient of discharge is smaller, venturimeter or

12

Orificemeter?

A. Orifice meter

2. What is the reason for smaller value of C d ?

A. There are no gradual converging and diverging flow passages as in

the case of venturimeter which results in a greater loss of energy and

consequent reduction of the coefficient of discharge for an orifice

meter

3. What is Orifice meter?

A. An orifice meter is another simple device used for measuring the

discharge through pipes.

4. What is the principle of Orifice meter?

A. Orifice meter also works on the same principle as that of venturi

meter i.e, by reducing the cross sectional area of the flow passage a

pressure difference between the two sections is developed and the

measurement of the pressure difference enables the determination of

the discharge through the pipe.

5. For discharge measurement through pipes which is having cheaper

arrangement and whose installation requires a smaller length?

A. Orifice meter

6. What are the parts of Orifice meter?

A. Flat circular plate with a circular hole

7. What is the thickness of the plate t?

d= diameter of the pipe

8. What is the range of bevel angle in orifice meter?

A. 300

to 450

( preferably 450

)

9. What is the diameter of the orifice?

A. It may very from 0.2 to 0.85 times the pipe diameter, but generally

the orifice diameter is kept as 0.5 times pipe diameter

10. Where two pressure taps are provided?

A. One on upstream side of the orifice plate and the other on

downstream side of the orifice plate.

2.11 POST-LAB QUESTIONS

11. Which diameter is less, orifice or pipe?

A. Orifice meter

12. What is vena contracta?

A. Smallest cross sectional area

13. At which section on the downstream side the pressure tap is provided

quite close to orifice plate?

A. At the section where the converging jet of fluid has almost the

smallest cross sectional area (which is known as vena contracta)

13

14. Where the velocity of flow is maximum and pressure is minimum?

A. At vena contracta

15. Maximum possible pressure difference that exists between upstream side

of the orifice plate and downstream side of the orifice plate is measured by

means of what?

A. Differential manometer

16. Where there is a greater loss of energy, whether in venturi meter or in

orifice meter?

A. In orifice meter

17. Why there is a greater loss of energy in orifice meter?

A. Because there is an abrupt change in the cross-sectional area of flow

passage

18. What is value of c d ?

A. It is the range of 0.6 to 0.68

19. What is the manometer liquid?

A. Mercury

20. When an orifice is called large orifice?

A. When head of liquid from the center of the orifice is less than 5 times

the

14

EXPERIMENT 3(B): CALIBRATION OF CONTRACTED TRIANGULAR NOTCH

3b.1 OBJECTIVE: To find out the coefficient of discharge of Triangular notch plate

3b.2 RESOURCES:

1.Notch tank 2.Sump Tank 3.Measuring tank 4.Notch plate 5.Rectangular notch

6. Supply pump set 7.Hook gauge 8. Stop Watch

3b.3 SPECIFICATIONS :

1. Sump Tank size : 1.2 m x 0.3 m x 0.42m S.S. Tank

2. Notch tank size : 1.0m x 0.2m x 0.18m S.S. Tank

3. Triangular notch :90˚ (Angle of the Notch)

4. Supply pump set : Pump is 25 x 25 mm2

size centrifugal monoset pump

with single phase, 2pole, 230 V, 50 Hz, ½ HP, 2880 RPM,

AC supply

5. Measuring tank Size : 0.6 m x 0.3 m x 0.5 m S.S. Tank

3b.4 DESCRIPTION OF RESOURCES:

1. Notch Tank: It is having steady arrangement with baffles and a provision

for fixing interchangeable notch plates. There are three baffles

2. Hook Gauge: It is fixed in notch tank top edge. The Hook gauge is kept in

vertical position with the help of spiral level. It is used to measure the

depth of water.

3. Measuring tank: It is a Stainless steel tank (S.S) with gauge glass and

scale arrangement for quick and easy measurements. A ball valve which is

outlet valve of measuring tank is provided to empty the tank.

4. Sump tank: It is also a S.S. tank to store sufficient fluid for experimentation

and arranged within the floor space of main unit. The sump tank should be

filled with fresh water leaving 25 mm space at the top.

3b.5 THEORY:

A notch is defined as an opening provided in the side of a tank ( or vessel)

such that the liquid surface in the tank is below the top edge of the opening.

Notches made of metallic plates are provided in narrow channels

(particularly in laboratory channels) in order to measure the rate of flow of liquid.

As such in general notches are used for measuring the rate of flow of liquid from a

tank or in a channel

15

The sheet of water flowing through a notch is known as the nappe (French

term meaning sheet) .The bottom edge of a notch over which the water flows is

known as the Sill or Crest, and its height above the bottom of the tank or channel is

known as Crest height.

The notches are usually classified according to the shape of the opening as

Rectangular notch, Triangular notch (or V-notch), Trapezoidal notch, Parabolic

notch and Stepped notch. The edges of all these notches are bevelled on the

downstream side so as to have sharp-edged sides and crest, resulting in minimum

contact with the flowing liquid. Since the liquid surface is always below the top

edge of the notch, a notch is usually provided with only a crest and sides with no

top edge.

Notches may also be classified according to the effect of the sides on the

nappe emerging from a notch, as notch with end contraction and notch without

end contraction or suppressed notch. Notches provided in the sides of tanks or

vessels are essentially the notches with end contraction. However, in a channel if

the crest length of the notch is less than the width of the channel then it is a notch

with end contraction. But if the crest length of the notch is equal to the width of

the channel then it is a notch without end contraction or a suppressed notch.

The expression for discharge over a Triangular notch is given by,

Where

L= width of the notch,(m)

= angle of the notch,(deg) h= head of water over the

notch,(m)

g= acceleration due to gravity

(m/s2)

16

3b.6 PROCEDURE:

1. Before starting the experiment, do priming of the pump to remove air bubbles

by pouring water into the priming device.

2. Open the inlet valve of the piping system of the pump

3. Keep the water level constant in the notch tank by operating three various

control valves and measure the initial height of water level by means of hook

gauge making sure that water is flowing on the notch plate.

4. Then increase the water flow in the notch tank and keep it constant in the

notch tank and keep it constant at one level and measure the height by means of

hook gauge.

5. Close the outlet valve of the measuring tank and note the time taken for 100

mm raise in the measuring tank. Repeat this process 3 to 4 times for various

water levels in notch tank.

6. Note down all the values and calculate co-efficient of discharge.

7. After conducting the experiment switch off the power supply.

3b.7 FORMULAE:

Actual discharge:

Actual discharge (Q act

)=

AR m

3/s

t

A= Area of measuring tank = 0.5 x 0.3m2

R = Rise of water level taken in meters ( say 0.1m or 10cm ) t = time taken for

rise of water level to rise ‘R’ in ‘t’ seconds

So, the actual discharge is measured with the help of measuring tank and by

noting the time for definite rise of water level of the tank.

Theoritical Discharge:

Theoritical Discharge of Triangular Nocth (Q ) = 8

th 15

5

Tan H 2

2

m 3 /s

g = acceleration due to gravity

L= Length of the notch in m

H = Height of the water surface over the notch in m

Ө = Angle of the Notch = 90˚

Coefficient of discharge:

Coefficient of discharge= 𝑸𝒂𝒄𝑸 =

Actual Discharge𝑻 𝒆𝒐 𝒄𝒂𝒍 𝑫 𝒄 𝒂 𝒆

2g

17

3b.8 OBSERVATIONS:

S. NO Depth of water Theoretic

al

discharge

(Q th ) in

m3

/s

Time for

100 mm

rise

Actual

discharg

e (Q act )

in m3

/s

Co-

efficient of

discharge

(C d

)

Hook guage reading

Initial

mm

Final

mm

Depth

m

h 1 h 2

H

Sample Calculations:

Area of the measuring tank = Time for 100 mm rise (t) in sec =

Actual discharge (Q act ) in m3/s =

Height of the water surface over the notch in m (H) =

Theoretical discharge (Q th ) in m3/s =

Coefficient of discharge of Triangular Notch (C d )

3b.9 PRECAUTIONS:

1. All the joints should be leak proof and water tight

2. Ensure the at gauge glass and meter scale assembly of the measuring tank is

fixed vertically and water tight

3. Ensure that the pump is primed before starting the motor

4. Ensure that the electric switch does not come in contact with water

5. The water filled in the sump tank should be 2” below the upper end

6. Check that hook gauge is firmly fixed and perpendicular to base

7. Ensure that the notch plate fitted in the notch tank should be vertical

8. Notch plate should be properly fixed and wing nuts should not be loose.

3b.10RESULTS:

1. Actual discharge of Triangular notch (Q act ) =

2. Theoretical discharge Triangular notch (Q th ) =

3. Co-efficient of discharge of Triangular notch(C d ) =

18

3b.11 PRE-LAB QUESTIONS:

1. What is notch?

A. A notch may be defined as a opening provided in the side of a tank (or

vessel) such that the liquid surface in the tank is below the top edge of

the opening.

2. Where notches made of metallic plates are used? And why?

A. In narrow channels in order to measure the rate of flow of liquid

3. What is the use of notch?

A. It is used to measure the rate of flow of liquid from a tank or in a channel

4. What is nappe?

A. The sheet of water flowing through a notch

5. Which word is nappe? What is the meaning?

A. French word means sheet

6. What is Sill or Crest?

A. Bottom edge of a notch over which water flows

3b.12 POST-LAB QUESTIONS:

7. What is crest height?

A. Notch height above the bottom of the tank is crest height

8. What are the types of notches according to shape of opening?

A. 1. Rectangular Notch 2.Triangular Notch (V Notch) 3. Trapezoidal

Notch 4. Parabolic Notch 5.Stepped Notch

9. On which the edges of all these notches are bevelled? And why?

A. On down stream side so as to have sharp edged sides and crest,

resulting in minimum contact with flowing liquid

10. What are the types of notches according to the effect of sides on the

nappe emerging from a notch?

A. 1. Notch with end contraction

2. Notch without end contraction or suppressed notch

11. What is notch with end contraction?

A. If the sides of a notch cause the contraction of nappe , then it is said to be

notch with end contraction.

12. What is notch without end contraction?

A. If there is no contraction of the nappe due to the sides then it is

known as a notch without end contraction

19

EXPERIMENT-4 : PIPE FRICTION FOR A GIVEN PIPE LINE

4.1 OBJECTIVE:To find the friction factor for a given pipe line.

4.2 RESOURCES: Pipe friction test rig, stopwatch.

4.3 THEORY:

Any fluid flowing through a pipe experiences resistance from the walls of the pipe due to

shear force viscosity.The amount of loss depends on the velocity of flow and area of

contact between the pipe surface and fluid.It also depend upon the type of flow i.e

Laminar or Turblent.This friction resistance causes loss of pressure head in the direction

of flow

The relation of dropof head derivedby Darchy’s-Weisbach is

Hf = 4.f.l.v2

2d.g

Coefficient of friction is given by f = 2gdhf

lv2

4.4 DESCIPTION OF THE RESOURCES: It consist of piping system with two pipe lines

of 20 mm (Square), and 15 mm (Round) with pressure tappings are connected to a

multiport manifold which in turn connected to manometer at a distance of 2.5 meters and

flow control valves.The whole unit is assembled to a steardy MS stand . A collecting tank

with a guage glass and scale fittings and assembly

When water flows through a pipe, a certain amount of energy (or pressure energy)has to

be spent to overcome the friction due to the roughness of the pipe surface. This

roughness effect depends on the roughness effect or frictional effect depends on the

material of the pipe and scale formation if any. If the surface is smooth the friction effect

is less first. For an old pipe due to the scale formation or chemical deposits the roughness

and hence the friction effect is higher.

Pipe line system in general includes several auxiliary components. In addition to types.

These components include the following:

1. Transitions or sudden expansion And contraction for changing pipe size.

2. Elbows and bends for changing flow directions.

These components introduce disturbances in the flow that cause turbulence and as

mechanical energy loss in addition to that which occur in basic type flow due to friction.

The energy loss although occurs over a finite distance, then viewed from the perspective

of an entire pipe system are localized near the component. Hence these losses are

referred to as local losses or minor losses. It should be remembered that these losses

sometimes are the dominant losses in piping system and hence the term minor losses is

a misnomer often.

4.4 EXPERIMENTAL PROCEDURE:-

1. Select the required pipe line

2. Connect the pressure tapping’s of the required pipe line to the manometer by

opening the appropriate pressure valves and closing all the pressure valves.

3. Note down the pressure difference from the manometer mercury column.

4. Collect the water in the collecting tank for 5 cm rise of level and note down the

time taken.

5. Repeat the experiment, at other flow rates.

20

Schematic diagram of friction losses through a pipe( Square and circular pipe):

4.5 TABULAR COLUMN:

(I)For square pipe:

S.NO Manometric head Time taken for h

cm raise of

water in tank t

‘s’

Discharge

(Q)

m3/s

Velocity

(v)

m/s

Friction

factor (f)

h1(Cm) h2(cm) h(cm)

1

2

3

4

5

21

(II)For circular pipe:

S.NO

Manometric head Time taken for h

cm raise of

water in tank t

‘s’

Discharge

(Q)

m3/s

Velocity

(v)

m/s

Friction

factor (f) h1(Cm) h2(cm) h(cm)

1

2

3

4

5

4.6 CALCULATIONS:

The distance between the pressure tapping’s and pipe line l=200 cm.

Diameter of round pipe =1.5 cm.

Loss of head due to friction h=( -1)

Area of the collecting tank A =50x50 cm2.

Where Sm :specific gravity of mercury -13.6

S: specific gravity of water -1

Rise of water level for 5 cm in collecting tank R = 5cm

Time taken for collecting water = t sec’s.

Discharge Q=(A*R/t) cm3/sec

Manometer Readings

Reading in the left limb=h1cm

Reading in the right limb=h2 cm

Darcy’s constant-f:

Head loss H= ℎ𝑙

4.7RESULT: The friction factor f for square pipe is ______________.

The friction factor f for circular pipe is ______________.

22

4.8 PRE-LAB QUESTIONS:

a. What is pipe?

A. A pipe is a closed circuit which is used for carrying fluids under

pressure

b. The fluid flowing by a pie is always subjected to what?

A. It is subjected to resistance due to shear forces between fluid

particles and the boundary walls of the pipe and between the

fluid articles themselves resulting from the viscosity of the fluid

c. What is frictional resistance?

A. The resistance to the flow of fluid is frictional resistance.

d. In overcoming the frictional resistance what is consumed?

A. Certain amount of energy possessed by the flowing fluid will be

consumed

e. What will be there in the direction of flow and it depends on what?

A. There will be some loss of energy in the direction of flow and

depends on the type of flow.

f. What are the types of flow of fluid in a pipe?

A. Laminar, turbulent

4.9 POST-LAB QUESTIONS:

g.On what the frictional resistance offered to the flow depends on?

A.Type of flow

h.What is the use of Darcy-Weisbach equation?

A. It is used for computing the loss of head due to friction in pipes

i.On what friction factor f depends upon? A. f is not a constant, but its value depends on the roughness

condition of the pipe surface and the Reynolds number of flow

j.Which is essential to determine the loss of head due to friction

correctly?

B. Correct estimation of the value of the factor

k. In addition to Darcy-Weisbach equation what are the other

formulae for head loss due to friction in pipes?

A. Chezy’s formula, Manning’s formula, Hazen-Williams formula

23

EXPERIMENT NO:5:DETERMINATION OF MINOR LOSSES OF HEAD

DUE TO SUDDEN CONTRACTION IN A PIPE LINE

5.1 OBJECTIVE: To determine the coefficient of Minor losses of head due to

sudden contraction

5.2RESOURCES:

1. Piping system 2.Sump Tank 3.Measuring Tank 4.Differential Manometer

5.Pump Set. 6. Stop Watch

5.3SPECIFICATIONS:

1. Sump tank size : 0.9 m x 0.45 m x 0.3 m S.S. tank

2. Measuring Tank Size : 0.6 m x 0.3m x 0.3 m S.S. Tank

3. Differential Manometer : 1 m range with 1mm scale of graduation

4. No. of pipes : 2 Galvanized Iron(GI)

5. Piping system sizes : 25 mm,12.5mm

6. Pressure taping distance : 0.5 m

7. Pump set : Pump is 25x25mm2

size, centrifugal,

moonset pump with single phase, 2pole,

220V, 1/2HP, 50 Hz, 2880 rpm, AC

supply.

5.4DESCRIPTION OF APPARATUS:

1. Piping system: piping system of size 25 mm diameter and 12.5 mm with a flow

control valve.

2. Sump tank: It is S.S. tank to store sufficient fluid for experimentation and

arranged within the floor space of main unit. The sump should be filled with fresh

water having 25 mm space at the top.

3. Measuring tank: It is also a S.S tank with gauge glass, a scale arrangement for

quick and easy measurements. A ball valve which is outlet valve of measuring tank

is provided to empty the tank.

4. Differential manometer: It is used to measure the differential head produced

by piping system.

5.Pump set: It is used to pump water from sump tank to measuring tank through

24

5.5 PROCEDURE:

1. Start the motor keeping the delivery valve close. Make sure that the ball

valve is fully open which is at the collecting tank

2. Slowly open the cocks which are fitted at sudden contraction end and make

sure that manometer is free from air bubbles

3. Make sure while taking the readings, that the manometer is properly primed.

Priming is the operation of removing the air bubbles from the pipes. Note down

the loss of head “hc” from the manometer scale.

4. Note down the time required for the rise of 10 cm (i.e 0.1 m) water in

the

collecting tank by using stopwatch. Calculate the discharge using below formula.

Discharge: The time taken to collect some ‘X’ cm of water in the collecting tank in

m3/sec

Q = AR

T

Where

A = Area of measuring (or) collecting tank = 0.3 x 0.3 m2

R = Rise of water level taken in meters (say 0.1 m

or 10 cm) t = time taken for rise of water level to

rise ‘R’ in‘t’ seconds

Calculate the velocity of the jet by following formula

V = Discharge / Area of pipe =Q/Am/sec Where

A = Cross sectional area of the pipe = Π / 4 * d2

d = diameter of the pipe

Calculate the coefficient of contraction for the given pipe by

hc = v2 / 2g * K

Where hc = loss of head due to sudden contraction =

(h1-h2)*12.6/100 m K = co-efficient for loss of head in

contraction

= [1/Cc - 1]2

V = Average Velocity of flow in m/sec

25

5. Repeat the steps 2 to 6 for different sets of readings by regulating the discharge

valve.

5.6 TABLE OF READINGS:

Type

of

Pipe

Diameter

of the

Pipe

‘d’

Area of

Pipe A

m2

Manometer

reading

Water

collected

in

collecting

tank

‘R’

Time for

(10 cm)

rise of

water

level t in

Sec.

h1 h2 hm

mm m cm of Hg cm m Sec

5.7 TABLE OF CALCULATIONS:

Actual

Discharge

Qact = A

R/t

Theoretica

l Velocity

Q

V =

a

hc

Coefficient

of

contraction

Cc

m3/sec m/sec m

5.8 PRECAUTIONS:

1. Ensure that the pump is primed before starting the motor

2. While doing the experiment on a particular pipe keep the other pipe line closed

3. Take the differential manometer readings without parallax error

4. Ensure that the electric switch does not come in contact with water

5. Remove air bubbles in differential manometer by opening air release valve

6. Ensure that opening and closing of manometer valves should be

done carefully to avoid leakage of mercury

7. Check that gauge glass and meter scale assembly of the measuring tank is fixed

vertically and water tight

8. Manometer should be filled to about half the height with mercury

9. Ensure that all valves on the pressure feed pipes and manometer should be closed

to prevent damage and over loading of the manometer

10. All the joints should be leak proof and water tight.

11. The water filled in the sump tank should be 2” below the upper end

5.9RESULTS:

Loss of head due to sudden contraction hc =

Coefficient of Contraction Cc =

26

5.10 PRE-LAB QUESTIONS:

a. Write the classification of various energy losses.

A. Major losses, minor losses

b. What causes major loss of energy?

A. Friction

c. Major loss of energy computed by which equation?

A. Darcy-Weisbach equation

d. What is the reason for the classification of loss of energy due to friction as

major loss?

A. In the case of long pipelines it is usually much more than the loss of

energy incurred by other causes.

5.10 POST-LAB QUESTIONS:

e. Due to what the minor losses of energy are caused?

A. Due to change in the velocity of flowing fluid

f. Why these are called minor losses?

A. In case of long pipes these losses are usually quite small as compared with

the loss of energy due to friction and hence these are termed. Minor losses

which may be neglected without serious error.

g. In where minor losses outweigh the friction loss?

A. In Short pipes

h. Write some minor losses which may be caused due to the change of velocity.

A. Loss of energy due to sudden enlargement

B. Loss of energy due to sudden contraction

C. Loss of energy at entrance to a pipe

D. Loss of energy at the exit from a pipe

E. Loss of energy due to gradual contraction or enlargement

F. Loss of energy in bends

G. Loss of energy in various pipe fit

27

EXPERIMENT-6 VERIFICATION OF BERNOULLI’S THEOREM

OBJECTIVE: To verify the Bernoulli’s theorem.

RESOURCES: Beroulli’s Equipment, stop watch.

DESCRIPTION: The apparatus consist of two reservoirs to store water to required head,

a closed conduit of varying cross-section, number of piezometers take along the path of

the conduit, to measure the pressure head at the point, and a controlling valve to control

rate of flow of water.A collecting tank is provided to find out the actual

discharge.According to bernoulli’s theorem the sum of the pressure head,velocity head,

datum head is constant at all points along a continuous conduit of friction flow.

PROCEDURE:

1. Open the inlet valve slowly and allow the water to flow from the supply tank.

2. Now adjust the flow to get a constant head in the supply tank to make flow in and

outflow equal.

3. Under this condition the pressure head will become constant in the piezometer

tubes. Note down piezometer readings.

4. Note down the quantity of water collected in the measuring tank for a given

interval of time.

5. Compute the area of cross-section under the piezometer tube.

6. Compute the values of velocity head and pressure head.

7. Change the inlet and outlet supply and note the reading.

8. Take at least three readings as described in the above steps.

SCHEMATIC DIAGRAM:

28

Throat

TABULARCOLUMN:

Trail-1:

S.N

o

Duct

poin

t

Pizeome

ter

Reading

time for

5cm rise

Discharge

Q

m3/s

Pressure

Head

m

Veloci

ty

Head

m

Datu

m

head

m

Total

Head

M

1

2

3

4

5

6

7

29

Trail -II

S.NO Duct

Point

Pizeomet

er

Reading

time

for 5cm

rise

Discharg

e

Q

m3/s

Pressur

e Head

m

Velocit

y Head

m

Datum

head

m

Total

Head

M

1

2

3

4

5

6

7

Trial-III

S.NO Duct

Point

Pizeomet

er

Reading

time

for

5cm

rise

Discharg

e

Q

m3/s

Pressur

e Head

m

Veloci

ty

Head

m

Datum

head

m

Total

Head

m

1

2

3

4

5

6

7

CALCULATIONS:

Pressure head =

Velocity head =

Datum head = Z = 0 (for this experiment)

Velocity of water flow = v

Q (Discharge) = [Volume of water collected in tank/time taken to collect water]

= [Area of tank × height of water collected in tank]/ t

Also

Q= velocity of water in pipe × area of cross section = v × Ax

Area of cross section (Ax) = At + [Ai−At ×LL ]

At = Area of Throat

Ai = Area of Inlet

Diameter of throt = 25mm

Diameter of inlet = 50mm

Ln= distance between throat and corresponding pizeometer

30

L=length of the diverging duct or converging duct = 300mm

Distance between each piezometer = 75mm

Total Head = 𝑃 + + Z

RESULT: By conducting experiment on Bernoulli’s apparatus and taking Trail-I,Trail-

II,Trail-III ,we have got constant total head.

Hence Bernoulli’s theorem is proved.

PRECAUTIONS:

1. Note the piezometer readings carefully.

PRE-LAB QUESTIONS:

1. What is z?

A. Potential energy per unit weight or potential head or datum head

2. What are the assumptions of Bernoulli’s equation?

A. 1) The fluid is ideal (i.e, viscosity is zero)

2) The flow is steady

3) The flow is incompressible

4) The flow is irrotational

3. What Bernoulli’s equation states?

A. It states that in a steady, ideal, irrotational flow of an incompressible fluid,

the total energy at any point of the fluid in constant

4. For which type of fluids Bernoulli’s equation is applicable?

A. For steady, irrotational flow of incompressible fluids

5. What is total head?

A. Sum of pressure head, velocity head, and potential head is known as total head

POST-LAB QUESTIONS:

1. What is Piezometric head?

A. Sum of pressure head and potential head

2. In Bernoulli’s equation each term represents what?

A. The energy per unit weight of the flowing fluid.

3. Why each term is called head?

A. The energy per unit weight of the fluid is expressed as N.m/N that is it has a

dimension of length and therefore it is known as head

31

EXPERIMENT NO-7 IMPACT OF JETS ON VANES

OBJECTIVE:To find the coefficient of impact of jet on vanes.

RESOURCES: Impact of jet on vanes experimental test rig, Flat vane, curved vane, Dead

weights, stop watch.

THEORY: A jet of fluid emerging from a nozzle has some velocity and hence it possesses

a certain amount of kinetic energy. If the jet strikes an obstruction placed in its path, it

will exert force on obstruction. This impressed force is known as impact of jet and it is

designated as hydrodynamic force, in order to distinguish it from the force due to

hydrostatic pressure. since a dynamic force is exerted by virtue of fluid motion, it always

involves a change of momentum, unlike a force due to hydrostatic pressure that implies

no motion.

PRINCIPLE: The impulse momentum principle may be utilized to evaluate the

hydrodynamic force exerted on a body by a fluid jet.

(1) When jet strikes a stationary Flat vane

In this case the flat vane is stationary and jet strikes on it at the middle and then splits in

two parts leaves the corners tangentially so

P=m/v

M=pa.s

Now dividing the equation with time t.

M/t=pa.s/t

M=ρav

Since we know that the impact of jet on vane is

F=Ma

F=M𝛥

F=(M/t).Δv

F=M(vinlet-voutlet)

F=M(v+vcosѳ)

F=ρav2(1+cosѳ)

The force of Impact will be maximum if the angle of declination is ѳ=90°

32

EXPERIMENTAL PROCEDURE:

1. Fix the vane to be tested inside the testing chamber by opening then transparent door

provided. Close the door and tighten the lock.

2. Note the initial reading on the scale.

3. Open the inlet water. The water jet from the nozzle strikes on vane gets deflected and

drains back to collecting tank.

4 .Close the collecting tank drain valve and note down the time taken for 2cm rise in

water level in the collecting tank. Open the drain valve.

5. Add dead weight to bring the pointer back to the initial reading on the scale. Note

down the dead weights.

6. Repeat the experiment for different flow rates by adjusting the position of the inlet

valves and for different vanes.

SCHEMATIC DIAGRAM:

TABULAR COLUMN:

(i)Flat vane:

S.NO Weight

(grams)

Fa(Actual

force) N

Ft(Theoretical

force( N)

Velocity

(m/s)

t

(Time

taken for

h cm rise

of water

in the

tank

Q= 𝑨×

m3/s K

1

100

2 150

3 200

4 250

33

(ii) curved vane:

S.NO Weight

(grams)

Fa(Actual

force) N

Ft(Theoretical

force( N)

Velocity

(m/s)

t

(Time

taken for

h cm rise

of water

in the

tank

Q= 𝑨×

m3/s K

1

100

2 150

3 200

4 250

CALCULATIONS:

Theoretical force (N): Ft= ρav2(1+cos φ)

For Flat vane= 𝜌𝑎

For curved vane=𝜌𝑎 1 + 𝑐𝑜𝑠ѳ

Where diameter of nozzle = 1cm

Area of collecting tank= 𝐴𝑅

m3/s

Where A= Area of collecting tank m2

R=rise in water level. m

Coefficient of impact on vanes= 𝐹 ℎ𝐹𝑎

RESULT:

The coefficient of impact of jet on vanes for Flat vane is ____________.

The coefficient of impact of jet on vanes for Curved vane is ___________.

PRECAUTIONS:

1.The flow should be steady and uniform

2.The readings on the scale should taken without error

3.The weight should be kept in the hanger slowly

34

PRE-LAB QUESTIONS:

1. Define Impact of jet?

2. Write the formula for force exerted by a jet of water on a stationary & moving

plate.

3. Write the formula for force exerted by a jet of water on a curved plate

. POST-LAB QUESTIONS:

1.What is the angle to be taken in case of a inclined vane?

2. What is the angle to be taken in case of a curved vane?

3.what type of force is developing in this process?

35

EGL

E

Jump V12/2g

V22/2g E2 E1

Flow

y2

y1 yg

EXPERIMENT NO. 8

STUDY OF HYDRAULIC JUMP

8.1 OBJECTIVE:

The purpose of this experiment is to observe the hydraulic jump phenomenon and to

compare measured flow depths with theoretical results based on the application of

continuity and momentum principles.

8.2 RESOURCES:

Glass walled flume with sluice gates & a spillway arrangement

Point gauges

Manometer & scales

Pump

8.3 THEORY

The hydraulic jump, also known as standing wave, is a rapid transition from

supercritical flow to subcritical flow. The transition is generally a turbulent process

can not be neglected. A hydraulic jump is

commonly used to dissipate energy, and reduce the downstream velocity. Figure 1

shows the variable included in a hydraulic jump.

Figure 1: Specific Energy Curve [2]

If supercritical flow occurs (by any hydraulic control such a gate) in a channel where

the normal flow condition is subcritical (due to slope, roughness, and flow rate), a

hydraulic jump will occur. In horizontal rectangular channels, the relationship

between the downstream and upstream depths is given by the following equation:

where,

y1 = upstream depth of water

(m) y2= downstream depth of

water (m) F1 = upstream

Froude number

36

F1 = where y = Depth of water (m)

Equation (1) is derived from the momentum equation in a controlled volume

between section 1 and 2 i.e. P1-P2= ρQ(V2-V1)

Where P1- and P2 are pressure at section-1 and V1 & V2 are velocity at

section 1 and 2 section-2 respectively

ρ = density of water in the controlled section Q = flow in the controlled

section

In addition, the energy loss is given by the following equation:

where, E1 = upstream energy, (m) E2= downstream energy, (m)

Δ E = energy loss, (m)

According to the U.S. Bureau Reclamation (USBR), a hydraulic jump can be classified

in undular, weak, oscillating, steady, and strong jump. Table 1 shows the

classification.

Table 1: Characteristics of Hydraulic Jump (USBR

1955) [1]

Nam

e

F1 Energy

dissipation

Undular jump 1.0 –

1.7

< 5%

Weak jump 1.7 –

2.5

5 – 15%

Oscillating jump 2.5 –

4.5

15 – 45%

Steady jump 4.5 –

9.0

45 – 70%

Strong jump > 9.0 70 – 85%

gy

V

37

8.4 EXPERIMENTAL PROCEDURE

A sluice gate installed in the flume, which has to be leveled used to generate the

hydraulic jump. The flume should be leveled. The sluice gate will create a

supercritical flow immediately after the gate, followed by a hydraulic jump, and

then a subcritical flow downstream of the hydraulic jump.

One vernier is located upstream of the hydraulic jump to measure the supercritical

depth, y1, and the other downstream of the hydraulic jump to measure the

subcritical depth, y2. The verniers are zeroed with the bed of the channel and have

to be moved depending on the location of the hydraulic jump.

The procedure consists of five (5) runs. Each run consists of a constant flow rate

and two (2) different opening gates. Measure the accurate flow rate, the upstream

depth, and the downstream depth

Run

Flow

rate

(L/s)

Initial opening

gate (mm)

Final opening

gate (mm)

1 0.5

8 14

2 1.

0

14 20

3 1.

5

20 26

4 2.

0

26 32

5 2.5

32 38

Use the following tables as guide to record the experimental data.

Experimental

data

Run Volume

(L)

Time (sec) Q

(L/s)

yg (mm) y1 (mm) y2 (mm)

1 10 8

10 14

2 10 14

10 20

3 10 20

10 26

4 10 26

10 32

5 10 32

10 38

38

8.5 CALCULATIONS

Calculate E1, E2, and .

Calculate F1.

Calculate y2/y1 from the experimental data.

Determine the theoretical value of y2/y1. Plot the theoretical y2/y1 and the experimental y2/y1 in one graph.

Classify the type of hydraulic jump using F1 and as criteria.

Analyze the results

8.6 RESULTS

Comment on the graph of the theoretical y2/y1 and the experimental y2/y1 Suggest other ways, different from a gate, to generate a hydraulic jump.

Name some applications where the loss of energy in a hydraulic jump would be

desirable [4].

39

EXPERIMENT -9 PERFORMANCE TEST ON PELTON WHEEL

9.1 OBJECTIVE: To draw the following characterstic curves of pelton wheel under constant

head .

9.2 RESOURCES:

1. Venturimeter 2. Stopwatch 3. Tachometer 4. Dead weight

9.3 DESCRIPTION:

Pelton wheel turbine is an impulse turbine, which is used to act on high loads and for

generating electricity. All the available heads are classified into velocity energy(i.e) kinetic

energy by means of spear and nozzle arrangement. Position of the jet strikes the knife-edge

of the buckets with least relative resistances and shocks. While passing along the buckets

the velocity of the water is reduced and hence an impulse force is supplied to the cups

which in turn are moved and hence shaft is rotated. Pelton wheel is an impulse turbine

which is used to utilize high heads for generation of electricity. It consists of a runner

mounted on a shaft. To this a brake drum is attached to apply brakes over the speed of the

turbine. A casing is fixed over the runner. All the available head is converted into velocity

energy by means of spear and nozzle arrangement. The spear can be positioned in 8 places

that is, 1/8, 2/8, 3/8, 4/8, 5/8 6/8, 7/8 and 8/8 of nozzle opening. The jet of water then

strikes the buckets of the Pelton wheel runner. The buckets are in shape of double cups

joined at middle portion. The jet strikes the knife edge of the buckets with least resistance

and shock. The jet is deflected through more than 160˚ to 170˚. While the specific speed

of Pelton wheel changes from 10 to 100 passing along the buckets, the velocity of water is

reduced and hence the impulsive force is supplied to the cups which in turn are moved and

hence the shaft is rotated. The supply of water is arranged by means of centrifugal pump.

The speed of turbine is measured with tachometer.

CONSTRUCTIONAL FEATURES:

CASING: casing is fabricated from MS Plates with integralbase is provided.

RUNNER:Runner is made of steel and machined precisely and fixed to horizontal shaft.The

bucket resembles to a hemispherical cup with a dividing wall inits center in the radial

direction of the runner.The buckets are arranged uniformly on the periphery of the

runner.The compact assemblyNickelplated to prevent corrosion and to have a smooth finish.

NOZZLE ASSEMBLY:Nozzle assembly consist essentially of a spear, a hand wheel and the

input pipe.The water from the supply pump is made to pass through the nozzle before it

enters the turbine.shaft is made of stainlesssteel and carries the runner and brake drum.

Brake arrangement :Brake arrangement consist of machined and polished brake drum,

cooling water pipes internal water scoop, discharge pipe spring balance, discharge

pipe,spring balance, belt arrangement supporting stand.

Base frame: Base frame is made is made of MS channel for sturdy construction and it is an

integral part of the casing.

TECHANICAL SPECIFICATIONS:

TURBINE:

1.Rated supply head-40m.

2.Discharge-660 Lpm.

3.Rated speed-800 Rpm.

4.Runner outside diameter-300m.

5.No of pelton buckets- 20 No’s

6.Brake drum diameter-300m

7.Power output-3.5 HP

SUPPLY PUMP:

40

Centrifugal pumpMultistage

FLOW MEASURING UNIT:

Venturimeter

Convergent diameter -65mm.

Throat diameter-39mm.

Pressure guage -7 kg/cm2.

9.4 PROCEDURE:

1.Gradually open the delivery valve of the pump.

2.Adjust the nozzle opening at about ½ th of the opening by oerating the spear valve by

Hand wheel.

3.The head should be made constant by operating the delivery valve and the head should

be maintained at constant value.

4.Observe the speed of the turbine using the tachometer.

5.Observe the readings of h1 and h2 corresponding the manometric fluid in the two

limbs,which are connected to the venturimeter.

6.Adjust the load on the brake drum;note the speed of the turbine using tachometer and

spring balance reading.

7. Repeat the experiment for different loadings

41

Fig: schematic representation of Pelton wheel

TABULAR COLUMN:

S.

N

O

Gat

e

ope

ning

Pressu

re

Gauge

(Kg/c

m2)

Vacuu

m

Gauge

(mm

of Hg)

Manometer

Reading Speed of

Break

drum

Dynamom

eter

‘N’(Rpm)

Spring

Balance Power

Output

(Po)

(KW)

Pow

er

Inp

ut

(Pi)

(K

W)

Efficienc

y

‘ Ƞ’ (%)

h1(c

m)

h2(c

m)

T1(kg

)

T2(

kg)

1

2

3

4

42

Electrical loading:

S.NO Load

(KW)

Voltammet

er

( V)

Current

(A)

Power

(KW)

Speed of Break

Drum

Dynamometer

‘N’ Rpm

Efficiency

‘Ƞ’ (%)

1

2

3

4

5

OBSERVATIONS:

Venturimeter inlet Diameter, d1= 65 mm.

Venturimeter inlet area, a1 =____________.

Venturimeter throat diameter ,d2= 39mm.

Venturimeter throat area, a2 = __________.

Speed (N) = ________ Rpm

Diameter of brake drum , D = 300mm

CALCULATIONS:

Inlet Pressure, P = Kg/cm2

Vaccum gauge =mm of Hg

Q= Discharge Q = Cd 𝑎 ×𝑎 ×√ ℎ√𝑎 2−𝑎 2

Where Cd -0.98

h-Manometric difference = h1-h2 [ -1]

where s1-specific gravity of mercury-13.6

s2-specific gravity of water-1

Total Head, H = Hs+Hd+Z

hs = suction head m

hd=delivery head=Pdx9.81x104

9.81x1000 m

Z= 2.2m

Output power (Po) = × ×6 watts

Input power (Pi) = (ρ×g×Q×h) W

T = (T1-T2) ×g × radius Of break drum N-m

T1=load applied on Brake drum dynamometer(Kg).

T2=load applied on Brake drum dynamometer(Kg).

Radius Of break drum = 0.15m.

N = speed of Brake drum Dynamometer (Rpm).

Efficiency of the turbine m%= Po/Pi

Electrical efficiency = e% = po / Pi

po= electrical output = V × I w.

43

GRAPHS:

1. speed vs. efficiency

2. Discharge vs. power input

3. Input power vs. Speed

4. Output power vs speed

RESULT:

The Efficiency of Pelton wheel at constant load is __________.The characteristics curves are

drawn.

PRECAUTIONS:

1.Delivery valve should closed before start of the turbine valve.

2. Don’t apply Mechanical loading when Electrical loading is performed.

3. Note down the readings carefully.

4. Maintain the gate opening constantly throught the experiment for (constant head

openings)

PRE-LAB QUESTIONS:

1.Classify turbines.

2.Pelton wheel is which type of turbine.

3.what is input energy given to turbine1. What are main components of Pelton turbine?

2. Draw velocity diagrams (at inlet and outlet) for Pelton blade

3. Why is Pelton turbine suitable for high heads?

4. What is the function of spear mechanism?

5. What is the normal range of specific speed of a Pelton turbine

6. What are the characteristics of Pelton wheel? What are their uses?

7. After the nozzle water has atmospheric pressure through out, then why is a casing

provided to the wheel?

8. Why not Pelton wheels are suitable for low heads?

POST-LAB QUESTIONS:

9. What are the methods available to govern the turbine.

10. What are main components of Pelton turbine?

11. Draw velocity diagrams (at inlet and outlet) for Pelton blade

12. Why is Pelton turbine suitable for high heads?

13. What is the function of spear mechanism?

14. What is the normal range of specific speed of a Pelton turbine

15. What are the characteristics of Pelton wheel? What are their uses?

16. After the nozzle water has atmospheric pressure through out, then why is a casing

provided to the wheel?

17. Why not Pelton wheels are suitable for low heads?

18. What are the methods available to govern the turbine

44

EXPERIMENT -10 PERFORMANCE TEST ON FRANCIS TURBINE

10.1 OBJECTIVE: To conduct load test on Francis turbine and to study the characteristics

of Francis turbine.

APPARATUS REQUIRED: U-tube manometer, Tachometer.

Supply pump:

Rated head-20 m,

Discharge-2000 Lps.

Normal speed-1440 Rpm

Power required-11.2 KW

Size of the pump-100x100 mm.

Pump Type: Centrifugal High speed single suction volute.

Francis turbine:

Rated supply head-20 m.

Discharge-2000 Lps.

Rated speed-1250 Rpm.

Runner diameter-150 mm.

Number of guide vanes-8.

Brake drum diameter-300 mm.

Flow measuring unit:

Manometer –U-tube differential column.

Size of venturimeter-100 mm

Throat diameter- 60mm.

DESCRIPTION:

The water from the penstock enters a scroll casing which completely surrounds the

runner.The purpose of the casing is to provide an even distribution around the

circumference of the turbine runner, maintaining an constant velocity of water.

In order to keep the velocity of water constant throught its path around the runner, the

cross-sectional area of casing is gradually decreased.The casing is made up of material

depending upon the pressure nto which it is subjected

From the scroll casing the water passes through the speed ring consist of upper and lower

ring

Held together by a series of fixed vanes called stay vanes. The number of stay vanes is

usually taken as half number of guide vanes.

The speed ring has two functions to perform.It directs the water to scroll casing to guide

vanes

Francis turbine consists of runner mounted on a shaft and enclosed in a spiral casing with

guide vanes. The cross section of flow between the guide vanes can be varied, known as

gate opening. It can be adjusted ¼, ½, ¾, or full gate opening. A brake drum is fixed to the

turbine shaft. By means of this drum the speed of the turbine can be varied. The discharge

can be varied by operating a throttle valve on the pipe line. The water after doing work

leaves the turbine through a draft tube and flows down into the tail race. A Venturimeter is

fitted to the pipe for measuring discharge.

PROCEDURE:

1. Keep the guide vane at required opening (say ½ th )

2. Prime the pump if necessary.

3. Close the main gate valve and start the pump.

4. Open the gate valve for required discharge

5. Open the brake drum cooling water gate valve for cooling the brake drum.

6. Note the Venturimeter pressure gauge readings

7. Note the inlet pressure gauge & outlet vacuum gauge readings

8. Note down applied weights spring balance.

45

46

OBSERVATIONS:

Venturimeter inlet Diameter, d= 100mm.

Venturimeter throat diameter d= 60mm.

Speed (N) =__________ Rpm

Radius of brake drum , R = 0.15 m

CALCULATION:

Inlet Pressure guage P = Kg/cm2

Outlet Vacuum guage V = mm of Hg

Total Head, H = Hs+Hd+Z m of Water

Hs= m

Hd=Pdx9.81x102 m

9.81x1000

Z=2.2 m

Q = Cd 𝑎 ×𝑎 ×√ ℎ√𝑎 2−𝑎 2 m3/s

Where Cd -0.98

Power input [Pi]= ρQgH KW

1000

ρ-Density of water 1000kg/m3.

Q- Flow rate m3/s

g-Acceleration due to gravity.9.81m/s

H- Total head.

Power output [Po] = 2ΠNT W

60

N- speed of Brake drum dynamometer.

Mechanical load

T= (T1-T2)x9.81x0.15 N-m. Efficiency Ƞ= power output

Power input

Electrical load

Power output =VxI KW

Power input = ρQgH KW

1000 Efficiency Ƞ= power output

Power input

RESULT: The efficiency of francis turbine=____________%.

Model graphs:

1. speed vs. efficiency

2. Discharge vs. power input

3. Input power vs. Speed

4. Output power vs speed

PREACUTIONS:

1.The gate valve should be closed before starting the turbine.

2. The gate valve should be ½ opening only.

2.Mechanical loading should be at consequitive intervals.

47

PRE-LAB QUESTIONS:

1.What is a reaction turbine.

2.what is difference between impulse and reaction turbine.

3.Specify the flow of the francis turbine.

.

POST-LAB QUESTIONS:

4.what head francis turbine used.

5.what is purpose of draft tube in reaction turbine.

6.What is cavitation

48

EXPERIMENT NO : 11 PERFORMANCE TEST ON CENTRIFUGAL PUMP

11.1 OBJECTIVE:: To find the efficiency and draw the performance curves of centrifugal

pump.

11.2 RESOURCES: Centrifugal pump test rig, energy meter to measure the input electrical

energy, pressure gauges (Suction and delivery), stop watch.

11.3 THEORY:

The pump which raises water from lower level to higher level by the action centrifugal force

is known as centrifugal pump. The pump lifts water because of atmospheric pressure acting

on the surface of the water.

A centrifugal pump is rotodynamic pump that uses a rotating impeller to increase the

pressure of the fluid. It works by rotational kinetic energy, typically from an electric motor

to an increase the static fluid pressure. They are commonly used to move liquid through a

piping system.

Fluid enters axially through the middle portion of the pump call the eye, after which it

encounters the rotating blades. It acquires tagential and radial velocity by the momentum

transfer with impeller blades and acquires additional radial velocity by centrifugal force.

11.4 PROCEDURE:

1. Prime the pump, close the delivery valve and switch on the unit.

2. Open the delivery vlave and maintain the requird delivery head.Note the reading.

3. Note the corresponding suction head pressure reading..

4. Measure the area of the collecting tank.

5. Close the drain the valve and note down the time taken for 10cm rise of the water level

in the collecting tank.

6. For different delivery heads repeat the experiment.

7. For every set of reading note the time taken for 10 revelutions of Energy meter.

49

Fig: centrifugal pump

11.5 TABULAR COLUMN:

S.NO Pressure

gauge

reading

Pd

(Kg/cm2

)

Vacuum

gauge

reading

mm of

Hg(Ps)

Time for

3 rev of

Energy

meter

seconds

(te)

Time for 10

cm rise in

collecting

tank (t)

seconds

Discharg

e (Q)

m3/sec

Input

Power

Pi

KW

Output

Power

Po

KW

Efficien

cy%

1

2

3

4

11.6CALCULATIONS:

The total effective head H in meters of Working of centrifugal pump

Total head H=Hs +Hd +Z

Since the delivery pressure is in kg/cm2 and suction gauge pressure are in mm of Hg the

total head developed by the pump to be converted in to meters of water column.

50

Where Hd=Delivery head

Hs =Suction head

Z=Datum level difference

Hs= m

Hd = Pdx9.81x102 m

9.81x1000

Z=2.2 m

Note: The velocity and the loss of head in the suction pipe are neglected

We know the discharge Q= 𝑨× m3/s

The work done by the pump is given by KW

Output power Po = ρQgH KW

1000

Input power Pi= 3600xn KW

ExtE

E- Energy meter constant=150

tE=time for 3 blinks of Energy meter.

n-total no of blinks.

The efficiency of the centrifugal pump=

Ƞ=Po/Pix100%.

11.7 GRAPHS:

1) Plot Pi and Po versus Speed N

2.Head versus Speed N

2) Speed versus Efficiency.

11.8RESULTS:

The performance characterstics of centrifugal pump are studied and the maximum efficiency

was found to be _________.

51

11.9 PRECAUTIONS:

1.Close the delivery valve before starting the pump.

2.Take readings correctly.

11.1. PRE-LAB QUESTIONS:

1.What is a pump.

2.What is a centrifugal pump .

3.what are forces involved in impeller.

4.What is priming.

11.2. POST-LAB QUESTIONS:

1.What is the device used to measure the speed ?

2.What is the use of pully arrangement in this setup ?

3.What is the efficiency range ?

52

EXPERIMENT NO :11(B) PERFORMANCE OF MULTI-STAGE CENTRIFUGAL PUMP

11(B) 1:OBJECTIVE To determine trhe efficiency of a multi stage centrifugal pump, plot

the operating characterstics and efficiency.

11(B) 2.RESOURCES :Multi-stage centrifugal pump, Pressure gauges at inlet and outlet,

stop watch.

11(B) 3.THEORY:

A pump may be defined as a mechanical device which mean interposed in a pipeline,

converts mechanical energy supplied to it from some external source into hydraulic energy,

thus resulting in the flow of liquid from low potential to high potential.

A centrifugal pump consist of impeller in a volute casing. The impeller has no of vanes

(curved) to the eye of the pump a suction pipe is connected.At the other end of this pipe a

foot valve with a strainer is connected.The water enters at the centre and flows outwards to

the pheriphery of the impeller.In the delivery side of pipe a delivery pipe with a delivery

valve is fixed.The energy supplied to the motor is measured by means of an energy meter.

Suction and delivery pressure gauges are fitted at the fitted to suction and delivery pipes

respectively near the pump.

A centrifugal pump may be driven with a constant speed or a variable speed motor.The flow

rate can be adjusted by opearating the valve provided on the delivery pipe line.The

pressure drop across the pump is measured by the pressure gauges.These centrifugal

pumps are coming under rotodynamic pump types and these pumps are used for more

discharge and it is working on the principle of forced vortex.

The main parts are impeller, casing suction pipe with strainer delivery pipe,foot valve with

strainer.

In case of the centrifugal pump, work done by the impeller on the water.The expression for

the work done by the impeller on the water is obtained by drawing velocity triangles at the

inlet and outlet of the impeller on the same as for the turbine.The water enters the impeller

radially at inlet for yhe best efficiency of the pump.Which means absolute velocity of water

at the inlet makes an angle 90° with the direction of the motion of the impeller at the inlet

and work done by the impeller.

53

11(B) 4.EXPERIMENTAL PROCEDURE:

1. Prime the pump with water if required.

2. Open the delivery gate valve completely.

3. Start the gate valve and adjust the gate valve to required pressure and delivery.

4. Note the following readings

(a) The pressure gauge reading kg/cm2

(b) The vacuum gauge reading mm of Hg.

(c) Time taken for every set of reading note the time taken for 3 rev. Energy meter.

(d) Close the drain valve and note down the time taken for 10cm rise of water in collecting

tank.

5. Take a set of reading for different pressures.

54

11(B) 5.TABULAR COLUMN:

S.NO Pressur

e

reading

Pressure

gauge

reading

Pd

(Kg/cm2

)

Vacuum

gauge

reading

mm of

Hg(Ps)

Time for 3

rev of

Energy

meter

seconds

(te)

Discharge

(Q)

m3/sec

Input

Power

Pi

KW

Output

Power

Po

KW

η% h1

(cm)

h2

(cm

)

1

2

3

4

11(B) 6.CALCULATIONS:

Flow rate of water Q = Cd x𝑎 ×𝑎 ×√ ℎ√𝑎 2−𝑎 2

d1 = dia. Of venture inlet = 65mm

d2 = dia. Of venture throat = 39mm

Cd = coefficient of discharge of venturimeter = 0.9

Where a1 = area of inlet of the venturimeter.

a2 = area of the venturimeter throat.

h= h1-h2 [ -1]

s1 -specific gravity of mercury-13.6.

s2 -specific gravity of water -1.

H = Total head of water (m)

H= suction head (hs) + delivery Head (hd) + Datum Head

Where hd = delivery head = Pd/ρg

hs = suction head

1. The work done by the pump is given by

Po = × × × H

Kw

Where,

ρ = Density of water (kg / m³) g = Acceleration due to gravity (m / s2)

H = Total head of water (m)

2. The input power Pi = 6 × E × t Kw

55

Where

N = Number of revolutions of energy meter disc

E = Energy meter constant = 150 (rev / Kw hr)

T = time taken for ‘Nr’ revolutions (seconds)

3. The efficiency of the pump = (Po/ Pi) ×100 %

11(B) 7.GRAPH:

1. Actual discharge Vs Total head

2. Actual discharge Vs Efficiency

3. Actual discharge Vs Input power

4. Actual discharge Vs Output power

11(B)8.RESULT: The efficiency of two stage centrifugal pump is ____________. The

performance characteristics are drawn.

11(B)9.PRECAUTIONS:

1.The delivery valve should be opened completely before starting the pump

11.(B)10. PRE-LAB QUESTIONS:

1.What is a pump.

2.What is a centrifugal pump .

3.what are forces involved in impeller.

4.What is priming.

11.(B)11. POST-LAB QUESTIONS:

1.What is the device used to measure the speed ?

2.What is the use of pully arrangement in this setup ?

3.What is the efficiency range ?

56

EXPERIMENT NO : 12 PERFORMANCE TEST ON RECIPROCATING PUMP

12.1 OBJECTIVE: To study the performance characteristics of Reciprocating pump and to

find slip.

12.2RESOURCES: Reciprocating test Rig, Pressure gauges at the inlet and delivery pipes,

Energy meter to measure the input electrical energy, stopwatch ,Tachometer.

12.3 THEORY: Reciprocating pumps are positive displacement pump as a definite volume

of liquid is trapped in a chamber which is alternatively filled from the inlet and empited at a

higher pressure through the discharge.

The fluid enters a pumping chamber through an inlet and is pushed out through outlet valve

by the action of piston.

They are either single acting independent suction and delivery strokes or double acting

suction and delivery both the directions.

Reciprocating pumps are self priming pumps and are suitable for very high head at low

flows.They deliver reliable discharge flows and is often used for metering duties because of

constancy of flow rate.

12.4DESCRIPTION:It consist of a double action reciprocating pump of size 25x20mm with

a air vessel coupled to 1HP, 1440Rpm

12.5PROCEDURE:

1.Keep the delivery valve open and switch on pump slowly close the delivery valve and

maintain a constant head.

2.Note the delivery and suction pressure gauge reading.

3.Note the time for 10 revolutions of Energy meter.

4.Note the time for 10cm rise in water level in collecting tank.

5.Note the speed of the pump.

5.Repeat the test for 4 other different head.

57

12.6 TABULAR COLUMN:

S.NO Pressure

gauge

reading

Pd

(Kg/cm2

)

Vacuu

m

gauge

reading

mm of

Hg(Ps)

Time

for 3

rev of

Energy

meter

(te)sec

Time for

10 cm

rise in

collecting

tank

(t)sec

Speed

NP

Rpm

Discharge

(Q)

m3/sec

Input

Power

Pi

KW

Output

Power

Po

KW

η%

1

2

3

4

5

12.7 CALCULATIONS:

Stroke length of the pump (L) = 0.045m

Bore (d) = 0.04m

Piston area (a) = (π/4) × (0.04)2

Area of the collecting tank (A) = 50 X 50 cm2

NP = speed of mortar in rpm

To find the percentage of slip = t – at × 100

Qt = theoretical discharge = L×a× p6 m/sec

Qa = Actual discharge = Q= 𝑨× m/sec

A = Area of the collecting tank

t = time for (h) rise in water level.

To find the overall efficiency of the pump = Po/Pi

Input power Pi = 6 × E × t Kw

Where

N = Number of revolutions of energy meter disc

E = Energy meter constant = 1600 (rev / Kw hr)

T = time taken for ‘Nr’ revolutions (seconds)

Output power Po = × × × H

Kw

Where,

58

ρ = Density of water = 1000 (kg / m³) g = Acceleration due to gravity = 9.81(m / s2)

H = Total head of water (m)

H = suction head (Hs) + delivery Head (Hd) + Datum Head

Where Hd = delivery head = Pdx9.81x104 m

ρxg

Hs = suction head m

Z= datum level difference = 2.2 m

12.8 GRAPHS:

1. Actual discharge Vs Total head

2. Actual discharge Vs Efficiency

3. Actual discharge Vs Input power

4. Actual discharge Vs Output power

12.9 RESULT: The efficiency of the reciprocating pump is__________. To study and draw

the characteristics curves.

12.10 PRE-LAB QUESTIONS:

1.What is the role of a piston rod ?

2.what type of pressure is going to develop in this pump ?

3.how many types of pumps are there ?

4.what type of head is available in this pump ?

12.11 POST-LAB QUESTIONS:

1.What is the input we are giving ?

2.What ois the output we r getting ?

3. what is the range of efficiency of this pump ?

59

TESTS BEYOND SYLLABUS COVERAGE

60

1. PERFORMANCE TEST ON KAPLAN TURBINE

OBJECTIVE: To draw the performance curves of the Kaplan Turbine and to determine the

specific speed of the turbine.

RESOURCES:

1. Kaplan Turbine test rig consist of

Kaplan turbine with casing, draft tube

Rope brake dynamometer

Motor

Centrifugal pump with suction pipe and delivery pipe fitted with venture

meter.

Pressure gauge

Sump

2. Tachometer.

3. Weights

BASIC EQUATIONS:

1. Efficiency, = Out put of turbine / Input of turbine

2. Out put of turbine = 2πNT /60 3. Input of turbine = wQH

Where

N = Speed in rpm of turbine in rpm

T = Torque acting on the shaft = WRe in N-m

w = Unit weight of water or Weight density of water in N/m3

Q = Discharge flowing through the turbine

H = Head acting on the turbine in m

W = Net brake load in N

Re = Effective radius of brake drum in m

THEORY:

A Kaplan turbine is a type of propeller turbine which was developed by the Austrian

engineer V. Kaplan. It is axial flow turbine which is suitable for low heads, and hence

requires a large quantity of water to develop a large amount of power. Reaction turbine and

hence operates in an entirely closed conduit from the head race to tail race.

The main components of Kaplan turbine are scroll casing; stay ring, arrangement of

guide vanes and the draft tube are similar to those of the Francis turbine. The runner of the

Kaplan turbine has four or six blades and it closely resembles ship’s propeller. The Kaplan

turbine runner blades can be turned about their own axis, so that their angle of inclination

may be adjusted while the turbine is in motion. For Kaplan turbine a high efficiency can be

61

maintained over a wide range of operating conditions. Specific speed varies from 257 to 858

( SI units).

62

OBSERVATIONS:

1. Venturi meter dimensions a) d1 = b) d2/d1 = c) d 2 = d) Cd =

e) K =

2. Dia. of brake drum dynamometer, D =

3. Rope diameter, d =

4. Mean diameter of brake drum, Dm =

5. Hanger weight, W0 =

TABULAR COLUMN:

S.No Gate

Opening

Inlet

Pressur

eP

kgf/cm2

Head of

the

turbine

m

Venturni meter

readings

Pr.

Head

diff. h

m

Discharg

e in m3/s

Wt. on

Hanger

W1,

kgf

Spring

Wt.

W2,

kgf

Torque

T, N-m

Speed

N, rpm

Output

KW

Input

KW

, %

p1,

kg/cm2

p2

kg/cm2

63

PROCEDURE:

1. The centrifugal pump is primed.

2. The gate opening is adjusted to the required opening. .

3. The delivery gate valve is completely closed.

4. The motor is switched on.

5. The delivery gate valve is adjusted to get the required head on the turbine.

6. The readings of pressure gauges attached to inlet and throat of venturi meter are noted.

7. The required weight is placed on the load hanger and the wheel is operated till the

weight on the load hanger is freely suspended.

8. The speed of the turbine is noted with the help of the tachometer.

9. The weight placed on the load hanger and load on spring balance are noted.

10. The procedure is repeated for various loads

11. The performance curves of the turbine are drawn.

PRECAUTIONS:

1. The gate valve is in fully closed position while starting the motor.

2. The priming valve and air cock are in closed position while starting the motor

GRAPHS:

1. Nu (x-axis) vs Qu (y-axis)

2. Nu (x-axis) vs Pu (y-axis)

3. Nu (x-axis) vs 0 (y-axis)

RESULTS:

1. The maximum efficiency of the turbine is __________

Corresponding Head _________________.

Corresponding Speed ______________.

Corresponding Power _________________.

2. The Specific Speed of the turbine is ______________.

PRE-LAB QUESTIONS:

1.What is a reaction turbine.

2.what is difference between impulse and reaction turbine.

3.Specify the flow of the francis turbine.

.

64

POST-LAB QUESTIONS:

4.what head francis turbine used.

5.what is purpose of draft tube in reaction turbine.

6.What is cavitation