SOM INDEX.doc

DEPARTMENT OF MECHANICAL ENGINEERING

CE6315 STRENGTH OF MATERIALS LABORATORY

(For IV-Semester Mechanical Engineering)

LABORATORY OBSERVATION BOOK

Academic year: 2014-2015

Prepared by: Verified by: Approved by: Name: Name: Name: Date: Date: Date:

CE6315– STRENGTH OF MATERIALS LABORATORY MANUAL

(FOR II B.E. MECHANICAL ENGINEERING STUDENTS)

DEPARTMENT OF MECHANICAL ENGINEERING

AS PER ANNA UNIVERSITY SYLLABUS

FROM REGULATION 2013

LABORATORY RECORD

2014 – 2015

Name of lab:

Department :

Certify that this is a bonafide record of work done by ……………………………. of

…………………………… class in the ………………….. Laboratory during the year

2014 -2015.

Signature of Lab in Charge Head of the Department

Submitted for the practical examination held on …………………………..

INTERNAL EXAMINER EXTERNAL EXAMINER

CE6461 FLUID MECHANICS AND MACHINERY LABORATORY

SYLLABUS R - 2013

LIST OF EXPERIMENTS

1. Determination of the Coefficient of discharge of given Orifice meter.

2. Determination of the Coefficient of discharge of given Venturi meter.

3. Calculation of the rate of flow using Rota meter.

4. Determination of friction factor for a given set of pipes.

5. Conducting experiments and drawing the characteristic curves of centrifugal pump/

submergible pump

6. Conducting experiments and drawing the characteristic curves of reciprocating pump.

7. Conducting experiments and drawing the characteristic curves of Gear pump.

8. Conducting experiments and drawing the characteristic curves of Pelton wheel.

9. Conducting experiments and drawing the characteristics curves of Francis turbine.

10. Conducting experiments and drawing the characteristic curves of Kaplan turbine.

INDEX

S.NO.

DATE NAME OF THE EXPERIMENTPAGE NO.,

MARKS STAFF SIGN

1Determination of the Co-efficient of discharge of given venturi meter

6

2Determination of the Co-efficient of discharge of given orifice meter 11

3Calculation Of The Rate Of Flow Using Roto Meter 16

4Determination Of Friction Factor Of Given Set Of Pipes 19

5Characteristics Curves Of Centrifugal Pump

25

6Characteristics Curves Of Reciprocating Pump

32

7 Characteristics Curves Of Gear Pump 37

8 Characteristics Curves Of Pelton Wheel 42

9 Characteristics Curves Of Francis Turbine

46

10 Kaplan Turbine Test Rig 52

Completed date:

Average Mark: Staff - in - charge

DETERMINATION OF THE CO EFFICIENT OFDISCHARGE OF GIVEN VENTURIMETER

Exp No: 1

Date:

AIM:

To determine the coefficient of discharge for liquid flowing through venturimeter.

APPARATUS REQUIRED:

1. Venturimeter

2. Stop watch

3. Collecting tank

4. Differential U-tube

5. Manometer

6. Scale

FORMULAE:

1. ACTUAL DISCHARGE:

Q act = A x h / t (m3 / s)

2. THEORTICAL DISCHARGE:

Qth = a 1 x a 2 x Ö 2 g h / Ö a 12 – a 2

2 (m3 / s)

Where:

A = Area of collecting tank in m2

h = Height of collected water in tank = 10 cm

a 1 = Area of inlet pipe in m2

a 2 = Area of the throat in m2

g = Specify gravity in m / s2

t = Time taken for h cm rise of water

H = Orifice head in terms of flowing liquid = (H1 ~ H2) (s m /s 1 - 1)

Where:

H1 = Manometric head in first limb

H2 = Manometric head in second limb

s m = Specific gravity of Manometric liquid

(i.e.) Liquid mercury Hg = 13.6

s1 = Specific gravity of flowing liquid water = 1

3. CO EFFICENT OF DISCHARGE:

Co- efficient of discharge = Q act / Q th

DESCRIPTION

For routine practical measurements of fluid flows, there exists a plentiful supply of flow

meters and flow-measuring devices as shown below.

Flow meters and flow measuring devices

For closed conduit flows For open Channel flows

Positive displacement Differential measurement (types) (types) Weirs Multiple current meter

Reciprocating Rotating Rotary Venturi- Orifices Nozzles& Piston meter Disc meter Piston& meter Elbow meter Vane meters

No flow meter or measuring technique is fool proof & hence the calibration of instrument

is highly necessary. Calibration of venturimeter means that determination of coefficient of

discharge (i.e., Cd) which truly indicates the discrepancy between actual and real or theoretical

discharge. The following sketches depict the parts of a venturimeter & also its principles of

construction:

Schematic of a venturimeter

The pressure difference between 1 and 2 is measured by the differential mercury

manometer. Venturimeter is highly applicable for the computation of flow rates in the closed

Pipes, including the measurement of gas flow rates. They yield a very high coefficient of discharge

(i.e., 0.95 to 0.99). Because of their constructional aspects and no suitability in congested spaces,

other flow meter are used.

PROCEDURE:

1. The pipe is selected for doing experiments

2. The motor is switched on, as a result water will flow

3. According to the flow, the mercury level fluctuates in the U-tube manometer

4. The reading of H1 and H2 are noted

5. The time taken for 10 cm rise of water in the collecting tank is noted

6. The experiment is repeated for various flow in the same pipe

7. The co-efficient of discharge is calculated

Ob

serv

atio

ns

Len

gth

of c

olle

ctin

g ta

nk =

L =

m

, b

read

th o

f co

llec

ting

tank

= B

m,

Pla

n ar

ea o

f ta

nk =

A =

L x

B =

m

2 .

Tab

ula

tion

s

Exp

erim

enta

l dat

a p

erta

inin

g to

Ven

turi

met

er 1

(i.e

., at

tach

ed t

o P

ipe

1)

Inle

t dia

met

er o

f V

entu

rim

eter

1 =

Pip

e 1

dia

= d

1 =

m

.

Thr

oat d

iam

eter

of

vent

urim

eter

1 =

d2 =

m

C/s

are

a of

inle

t = a

1 =

m

2

C/s

are

a of

thro

at =

a2 =

m

2

Co-

effi

cien

t of

d

isch

arge

C

d

(no

un

it)

Th

eore

tica

l d

isch

arge

Q

th

in m

3 / s

M

ean

Cd

=

Act

ual

d

isch

arge

Q

act

in m

3 / s

Tim

e ta

ken

for

h

cm

ris

e of

wat

er t

in s

ec

Man

omet

ric

hea

d

H=

(H1~

H2)

x 1

2.6

in m

of

wat

er

Man

omet

ric

read

ing

H2

cm

of H

gH

1 cm

of

Hg

Dia

met

er

in m

m

S.n

o

GRAPH :

Coefficient of discharge from the graph of Qa v/s Qth:

Slope = Cd = Constant.

Qact

Qth

Coefficient of discharge from the graph = Cd =

RESULT

Coefficient of discharge of the venturimeter (Cd)

by direct computation = ___________

by graph. = ___________

DETERMINATION OF THE CO-EFFICIENT OFDISCHARGE OF GIVEN ORIFICE METER

Exp No : 2Date :

AIM:To determine the co-efficient discharge through orifice meter

APPARATUS REQUIRED:

1. Orifice meter

2. Differential U tube

3. Collecting tank

4. Stop watch

5. Scale

FORMULAE :


Q act = A x h / t (m3 / s)

2. THEORTICAL DISCHARGE:

Q th = a 1 x a 0 x Ö 2 g h / Ö a 12 – a 0

2 (m3 / s)

Where:

A = Area of collecting tank in m2

h = Height of collected water in tank = 10 cm

a 1 = Area of inlet pipe in, m2

a 0 = Area of the orifice in m2

g = Specify gravity in m / s2

t = Time taken for h cm rise of water

H = Orifice head in terms of flowing liquid = (H1 ~ H2) (s m / s 1 - 1)

Where:

H1 = Manometric head in first limb

H2 = Manometric head in second limb

s m = Specific gravity of Manometric liquid

(i.e.) Liquid mercury Hg = 13.6

s1 = Specific gravity of flowing liquid water = 1

3. CO EFFICENT OF DISCHARGE:

Co- efficient of discharge, Cd = Q act / Q th

DESCRIPTION:

For routine practical measurements of fluid flows, there exists umpteen supply of

flow meters and flow-measuring techniques as mentioned in the previous experiment (Refer the

venturimeter Expt.). Calibration of orifice meter means that determination of coefficient of

discharge (i.e., Cd) which reveals the difference between actual and theoretical discharge. The

following sketches depict the orifice and also its principle of construction.

Schematic of streamlines in an Orifice meter(During fluid flow)

Although the basic principle for both venturimeter and orifice meter is somewhat same, the

flow separation and energy dissipation is predominant in orifice meter due to the formation of vena

contracta (i.e., where the jet of water contracts w.r.t. the diameter of orifice) at the downstream of

flow. Hence, orifice meters yield a comparatively lesser value of Cd than for venturimeter.

Orifices serves many purposes in engineering practice other than the metering of fluid

flow, but the study of the orifice as a metering device will allow the application of principles to

other problems. Orifices may be used in closed conduits or fitted to the containers for discharging

the fluids. They are highly preferred over venturimeter because of its simplicity in construction and

utility in space congestions, in spite of this lower Cd values.

PROCEDURE:

1. The pipe is selected for doing experiments

2. The motor is switched on, as a result water will flow

3. According to the flow, the mercury level fluctuates in the U-tube manometer

4. The reading of H1 and H2 are noted

5. The time taken for 10 cm rise of water in the collecting tank is noted

6. The experiment is repeated for various flow in the same pipe

7. The co-efficient of discharge is calculated

Ob

serv

atio

ns

Len

gth

of c

olle

ctin

g ta

nk =

L =

m

,

brea

dth

of c

olle

ctin

g ta

nk =

B

m

,

Pla

n ar

ea o

f ta

nk =

A =

L x

B =

m

2 .

Tab

ula

tion

s

Exp

erim

enta

l dat

a p

erta

inin

g to

ori

fice

met

er 1

(i.e

., at

tach

ed t

o P

ipe

1)

Dia

met

er o

f P

ipe

1 =

d1 =

m

,

Dia

met

er o

f or

ific

e 1

= d

2 =

m

C/s

are

a of

inle

t = a

1 =

m2

C/s

are

a of

ori

fice

= a

0 =

m2

Co-

effi

cien

t of

d

isch

arge

C

d

(no

un

it)

Th

eore

tica

l d

isch

arge

Q

th

in m

3 / s

M

ean

Cd

=

Act

ual

d

isch

arge

Q

act

in m

3 / s

Tim

e ta

ken

for

h

cm

ris

e of

wat

er t

in s

ec

Man

omet

ric

hea

d

H=

(H1~

H2)

x 1

2.6

in m

of

wat

er

Man

omet

ric

read

ing

H2

cm

of H

gH

1 cm

of

Hg

Dia

met

er

in m

m

S.n

o

GRAPH :

Coefficient of discharge from the graph of Qa v/s Qth:

Slope = Cd = Constant.

Qact

Qth

Coefficient of discharge from the graph = Cd =

RESULT:

Coefficient of discharge of the orifice meter (Cd)

by direct computation = __________

by graph. = __________

CALCULATION OF THE RATE OF FLOW USING ROTOMETER

Exp No: 3

Date:

AIM:

To determine the percentage error in Rotometer with the actual flow rate.

APPARATUS REQUIRED:

1. Rotometer setup

2. Measuring scale

3. Stopwatch.

FORMULAE:


Q act = A x h/ t (m3 / s)

Where:

A = Area of the collecting tank (m2)

h= 10 cm rise of water level in the collecting tank (10-2 m).

t = Time taken for 10 cm rise of water level in collecting tank.

CONVERSION:

Actual flow rate (lit / min), Qact = Qact x 1000 x 60 lit /min

Rotometer reading ~ Actual x 100 % Percentage error of Rotometer =

Rotometer reading

= R ~ Qact / R x 100 %

DESCRIPTION:

A Roto meter is a device used for measuring the rate of flow of water flowing through the

pipe. A Roto meter consists of a tapered metering glass tube, inside of which is located a rotor

(float) of the meter. The tube is provided with suitable inlet and outlet connections. The float tube

has a specific gravity higher than that of the fluid to be metered. The spherical slots cut on a part of

the float causes it to rotate slowly about the axis of the tube and keep it centered. With increase in

the flow rate, the float rises in the tube and there occurs an increase in the annular area between the

float and the tube. The float rides may be higher or lower depending on the flow rate.

Glass tube Rotometer

PROCEDURE:

1. Switch on the motor and the delivery valve is opened

2. Adjust the delivery valve to control the rate in the pipe

3. Set the flow rate in the Rotometer, for example say 50 litres per minute

4. Note down the time taken for 10 cm rise in collecting tank

5. Repeat the experiment for different set of Rotometer readings

6. Tabular column is drawn and readings are noted

7. Graph is drawn by ploting Rotometer reading Vs percentage error of the Rotometer

Ob

serv

atio

ns

Len

gth

of c

olle

ctin

g ta

nk =

L =

m

, B

read

th o

f co

llec

ting

tank

= B

m,

Pla

n ar

ea o

f ta

nk =

A =

L x

B =

m

2

Tab

ula

tion

s

Exp

erim

enta

l dat

a p

erta

inin

g to

Rot

omet

er

Per

cen

tage

Err

or o

f R

otom

eter

I

n %

Act

ual

dis

char

geQ

act

in lp

m

Tim

e ta

ken

for

10c

m

rise

of

wat

er in

tan

kt

in s

ec

Act

ual

Dis

char

geQ

act

In m

3 /sec

Rot

omet

erR

ead

ing

in lp

m

S.n

o

GRAPH :

Percentage error of rotometer from the graph by Qact vs R

Qact

R

The percentage error of the Rotometer by graph is =

RESULT :

The percentage error of the Rotometer was found to be

by direct computation = ___________

by graph. = ___________

DETERMINATION OF FRICTION FACTOR OF

GIVEN SET OF PIPES

Exp No: 4

Date:

AIM:

To find the friction factor, ‘f ’ for the given pipe.

APPARATUS REQUIRED:

1. A pipe provided with inlet and outlet and pressure tapping

2. Differential u-tube manometer

3. Collecting tank with piezometer

4. Stopwatch

5. Scale

FORMULAE:

1. FRICTION FACTOR ( F ):

f = 2 x g x d x h f / l x v2

Where,

g = Acceleration due to gravity, (m / sec2)

d = Diameter of the pipe

l = Length of the pipe, (m)

v = Velocity of liquid following in the pipe, (m / s)

h f = Loss of head due to friction, (m)

= h1 ~ h2

Where

h1 = Manometric head in the first limbs

h2 = Manometric head in the second limbs


Q = A x h / t (m3 / sec)

Where

A = Area of the collecting tank, (m2)

h = Rise of water for 5 cm, (m)

t = Time taken for 5 cm rise, (sec)

3. VELOCITY:

V = Q / a (m / sec)

Where

Q = Actual discharge, (m3/ sec)

A = Area of the pipe, (m2)

DESCRIPTION:

In steady incompressible flow in a pipe irreversibilities are expressed in terms of a head

loss, or drop in grade line. Losses, or irreversibilities, cause this line to drop in the direction of

flow. Experiments on the flow of water in long, straight, cylindrical pipes indicated head loss

varied directly with velocity head and pipe length, and inversely with pipe diameter (as shown in

figure)

Schematic of Pipe Friction

The Darcy–Weisbach equation is probably more rationally based than other empirical

formulations and has received wide applications & acceptance. The equation is given by h f =

flv2/2gd, where, hf is loss due to friction in m; f is dimensionless friction factor; V is the average

velocity across the C/S in m/s; d is pipe diameter in m. The friction factor f also depends upon

fluid properties (such as density and viscosity) and also on material roughness.

The main significance of friction factor is to assess the extent of energy loss in pipe flow,

while designing a pipe, pump to pressurize the fluid in pipes and other similar situations.

PROCEDURE :

1. The diameter of the pipe is measured and the internal dimensions of the collecting tank

and the length of the pipe line is measured

2. Keeping the outlet valve closed and the inlet valve opened

3. The outlet valve is slightly opened and the manometer head on the limbs h1 and h2 are

noted

4. The above procedure is repeated by gradually increasing the flow rate and then the

corresponding readings are noted.

Ob

serv

atio

ns

Len

gth

of c

olle

ctin

g ta

nk =

L =

m

, br

eath

of

coll

ecti

ng ta

nk =

B =

m,

Pla

n ar

ea o

f ta

nk =

A =

L x

B =

m2 .

Dia

met

er o

f P

ipe

1 =

d1 =

m,c

/s a

rea

= a

1 ==

m2

Len

gth

of P

ipe

unde

r co

nsid

erat

ion

= l=

m

Tab

ula

tion

s

(a)

Exp

erim

enta

l dat

a p

erta

inin

g to

Pip

e 1

Dia

met

er o

f P

ipe

1 =

d1 =

m

. and

a1 =

m

2 .

Fri

ctio

n

fact

orf

x 10

-2

(no

un

it)

V2

m2 /

s 2

M

ean

f =V

eloc

ity

V m/s

Act

ual

d

isch

arge

Qac

t

m3 /

s

Tim

e fo

r 10

cm r

ise

of w

ater

t s

ec

Man

omet

er r

ead

ings h

f =

(h1-

h2)

x 1

2.6

in m

h2

cm o

f H

g

h1

cm o

f H

g

Dia

met

er

of

pip

e

in m

m

S.n

o

Friction factor from the graph of hf v/s V2/2g

Slope = hf/(Va2/2g) = Const.

hf

Va2/2g

from the graph

Slope = fl/d

f = slope * d/l

RESULT Friction factor for the given pipe material (i.e., ‘f’)

By computation = ____________

By graph = ___________

CHARACTERISTICS TEST ON CENTRIFUGAL PUMP

Exp No: 5

Date:

AIM :To study the performance characteristics of a centrifugal pump and to determine the

characteristic with maximum efficiency.

APPARATUS REQUIRED :

1. Centrifugal pump setup

2. Meter scale

3. Stop watch

FORMULAE :


Q act = A x h/ t (m3 / s)

Where:

A = Area of the collecting tank (m2)

h = 10 cm rise of water level in the collecting tank

t = Time taken for 10 cm rise of water level in collecting tank.

2. TOTAL HEAD:

H = Hd + Hs + Z

Where:

Hd = Discharge head, meter

Hs = Suction head, meter

Z = Datum head, meter

3. INPUT POWER:

I/P = (3600 ´ N ´ 1000) / (E ´ T) (watts)

Where, N = Number of revolutions of energy meter disc

E = Energy meter constant (rev / Kw hr)

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

4. OUTPUT POWER:

O/ P = ρ x g x Q x H / 1000 (watts) Where, ρ = Density of water (kg / m³)

g = Acceleration due to gravity (m / s2)

H = Total head of water (m)

5. EFFICIENCY: ho = (Output power o/p / input power I/p) ´ 100 %

Where,O/p = Output power kW

I/ p = Input power kW

DESCRIPTION: Pumps add energy to liquids; Turbo pumps are radial flow, axial flow or a

combination of two, called mixed flow. For high heads the radial (centrifugal) pump, frequently

with two or more stages (two or more impellers in series), is best adopted. For large flows under

small heads the axial flow pump or blower is best suited. The mixed flow pump is used for

medium head and medium discharge. The centrifugal pump is so called because the pressure

increase within its rotor due to centrifugal action is an important factor in its operation. In brief, it

consists of an impeller rotating within a case as shown in Fig. given below:-

used for lifting water from deep tube wells

used for liftingwater from deepwells, especially when the alignment is poor

Cut-view of Vortex and Volute Centrifugal Pump

Fluid enters the impeller in the center portion, called the eye, flows outwardly and is discharged

around the circumference into a casing. During flow through the rotating impeller the fluid

receives energy from the vanes, resulting in both pressure and absolute velocity. Since a large part

of the energy of the fluid having the impeller is kinetic, it is necessary to reduce the absolute

velocity into transformation pressure head. This is accomplished in the volute casing surrounding

the impeller or in flow through diffuser vanes. Following is the classification of centrifugal pumps

with their applications.

Centrifugal Pump(very widely used in water supply &waste water schemes)

Single stage (usual head) Multistage (when the head & discharge is large)

Volute pump Diffuser pump

Radial flow Mixed flow Deep well Submersible pump Turbine pump

Open type Closed type(to handle slurries (to handle treated Raw water &others) & unturbid water)

PRIMING:

The operation of filling water in the suction pipe casing and a portion delivery pipe for

the removal of air before starting is called priming.

After priming the impeller is rotated by a prime mover. The rotating vane gives a

centrifugal head to the pump. When the pump attains a constant speed, the delivery valve is

gradually opened. The water flows in a radially outward direction. Then, it leaves the vanes at the

outer circumference with a high velocity and pressure. Now kinetic energy is gradually converted

in to pressure energy. The high-pressure water is through the delivery pipe to the required height.

PROCEDURE:

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

2. Open the delivery valve and maintain the required delivery head

3. Note down the reading and note the corresponding suction head reading

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

collecting tank

5. Measure the area of collecting tank

6. For different delivery tubes, repeat the experiment

7. For every set reading note down the time taken for 5 revolutions of energy meter disc.

Ob

serv

atio

nL

engt

h of

the

coll

ecti

ng ta

nk=

L =

m

Bre

adth

of

the

coll

ecti

ng ta

nk =

B =

m

Pla

n ar

ea o

f ta

nk A

= L

x B

= =

m2

Ene

rgy

met

er c

onst

ant

K =

imp/

kwh

Dis

tanc

e be

twee

n th

e su

ctio

n an

d de

live

ry g

auge

s =

Dat

um h

ead

=Z

= m

Tab

ula

tion

Exp

erim

enta

l dat

a p

erta

inin

g to

c.f

. pu

mp

(si

ngl

e st

age

oper

atio

ns)

:

h %

Ou

tpu

tP

ower

(Po)

wat

t

Inp

ut

Pow

er

(Pi )

wat

t

Act

ual

Dis

char

ge

(Qac

t)

m3 \s

ec

Tim

e ta

ken

for

N

r re

volu

tion

t S

Tim

e ta

ken

fo

r ‘h

’ ri

seof

wat

er(t

)

S

Tot

alH

ead

(H)

m o

f w

ater

Del

iver

yH

ead

(Hd

)

m o

f w

ater

Del

iver

yG

auge

Rea

din

g(h

d)

m o

f w

ater

Su

ctio

n

hea

d

Hs

m o

f w

ater

Su

ctio

n

gau

ge

Hs

m o

f w

ater

S.

no

Performance of C.F. Pump through graph

Though some C.F. pumps are driven by variable speed motors the usual mode of

operation of pump is at constant speed and typical characteristics of a C.F. Pump for such

operation as shown in figure.

Optimum head = m

Normal head = m

Optimum discharge = m3/s

& Normal discharge = m3/s

Graph H O/P h1. Actual discharge Vs Total head

2. Actual discharge Vs Efficiency

3. Actual discharge Vs Output power

Q

RESULTPerformance of given centrifugal pump (single stage)

Optimum head = m

Normal head = m



CHARACTERISTICS CURVES OF RECIPROCATING PUMP

Exp No: 6

Date:

AIM:To study the performance characteristics of a reciprocating pump and to determine the

characteristic with maximum efficiency.

APPARATUS REQUIRED:

1. Reciprocating pump

2. Meter scale

3. Stop watch

FORMULAE:


Q act = A x y / t (m3 / s)

Where: A = Area of the collecting tank (m2)

y = 10 cm rise of water level in the collecting tank

t = Time taken for 10 cm rise of water level in collecting tank

2.TOTAL HEAD:

H = Hd + Hs + Z

Where:

Hd = Discharge head; Hd = Pd x 10, m

Hs = Suction head; Pd = Ps x 0.0136, m

Z = Datum head, m

Pd = Pressure gauge reading, kg / cm2

Ps = Suction pressure gauge reading, mm of Hg

3.INPUT POWER:

Pi = (3600 ´ N) / (E ´ T) (Kw)

Where, N = Number of revolutions of energy meter disc

E = Energy meter constant (rev / Kw hr)

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

4. OUTPUT POWER:

Po = ρ x g x Q x H / 1000 (Kw) Where,

ρ = Density of water (kg / m³)

g = Acceleration due to gravity (m / s2)

H = Total head of water (m)

Q = Discharge (m3 / sec)

5.EFFICIENCY: ho = (Output power po / input power pi) ´ 100 %

Where,Po = Output power KW

Pi = Input power KW

DESCRIPTION

Reciprocating pumps, the name given to the pumping machinery in which the essential

working components are cylinder and plunger or piston (refer Fig.1). These small pumps have

single cylinder and are single acting.(i.e., they suck the liquid to be pumped during forward stroke

and deliver it during backward or return stroke). Large industrial pumps can be multi cylinder and

double acting. Since forward and backward strokes are completed during one complete revolution

of crank and since the pump is single acting, rate of liquid delivered per second is given by AlN .

Sche

mati c

Diagram of a Single-cylinder and

Single acting Reciprocating pump

Usually due to leakage losses, the actual discharge is somewhat less than theoretical

discharge and the difference between actual and theoretical discharges is known as ‘slip’ of pump

which is given by,

Percentage slip= Theoretical discharge –Actual discharge x 100

Theoretical discharge

The variation between the pressure in the cylinder and volume swept by piston for one

complete revolution is known as indicator diagram. Figure 2 represents the indicator diagram and

in that; ab represents a constant pressure of (Pa/r-hs ) acting during suction or forward stroke , cd

represents a constant pressure of hd acting during delivery or backward stroke, and bc and da are

imaginary lines that represent the instantaneous jump at the end of suction and delivery strokes ,

respectively.

Small hand operated pumps, such as cycle and football pumps, kerosene pumps, village

well pumps; pumps in milk shops and pumps in hydraulic jack are some applications of the

reciprocating pumps. Reciprocating pumps for industrial uses have now almost become obsolete

because of their capital cost and maintenance cost when compared to centrifugal pumps. However,

they are also less efficient. Hence, centrifugal pumps dominate these pumps.

Ob

serv

atio

ns

Len

gth

of th

e co

llec

ting

tank

= L

=m

Bre

adth

of

the

coll

ecti

ng ta

nk =

B =

m

Pla

n ar

ea o

f ta

nk =

A=

L *

B =

m2

Dis

tanc

e be

twee

n th

e ga

uges

= D

atum

hea

d =

z=

m

& E

nerg

y m

eter

con

stan

t = K

=

rev/

kwh

Tab

ula

tion

Exp

erim

enta

l dat

a p

erta

inin

g to

th

e si

ngl

e cy

lin

der

an

d s

ingl

e-ac

tin

g re

cip

roca

tin

g p

um

p:

h %

Ou

tpu

t p

ower

Po

Kw

Mea

n =

Inp

ut

pow

er

Pi

Kw

Tim

e ta

ken

fo

r N

rev

of

en

ergy

m

eter

dis

c

t

sec

Act

ual

d

isch

arge

Qac

t

m³/s

Tim

e ta

ken

fo

r 10

cm

of

rise

of

wat

er

in t

ank

t sec

Tot

al

hea

d

H m

Dat

um

h

ead

Z

m

Su

ctio

n

hea

d

Hs

=

Ps

x .0

136

m

Del

iver

y h

ead

Hd=

Pd

x10.

0

m

Su

ctio

n

pre

ssu

re

read

ing

Ps

mm

of

Hg

Del

iver

y p

ress

ure

re

adin

g

Pd

kg

/ cm

2

S. n o

PROCEDURE:

1. Close the delivery valve and switch on the unit

2. Open the delivery valve and maintain the required delivery head

3. Note down the reading and note the corresponding suction head reading

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

collecting tank

5. Measure the area of collecting tank

6. For different delivery tubes, repeat the experiment

7. For every set reading note down the time taken for 5 revolutions of energy meter disc.

PERFORMANCE OF RECIPROCATING PUMP THROUGH GRAPH

Though some reciprocating pumps are driven by variable speed motors, the usual

mode of operation of pump is at constant speed and typical characteristics of a Reciprocating

pump for such operation is as shown in figure.

Optimum head = m

Normal head = m



Graph H O/P h1. Actual discharge Vs Total head


3. Actual discharge Vs Output

Q

RESULTPerformance of given centrifugal pump (single stage)

Optimum head = m

Normal head = m



CHARACTERISTICS CURVES OF GEAR OIL PUMP

Exp No: 7

Date:

AIM:

To draw the characteristics curves of gear oil pump and also to determine efficiency of

given gear oil pump.

APPARATUS REQUIRED:

1. Gear oil pump setup

2. Meter scale

3. Stop watch

FORMULAE: 1. ACTUAL DISCHARGE:

Qact = A x y / t (m³ / sec)

Where, A = Area of the collecting tank (m²)

y = Rise of oil level in collecting tank (cm)

t = Time taken for ‘h’ rise of oil in collecting tank (s)

2. TOTAL HEAD:

H = Hd + Hs + Z

Where

Hd = Discharge head; Hd = Pd x 12.5, m

Hs = Suction head; Pd = Ps x 0.0136, m

Z = Datum head, m

Pd = Pressure gauge reading, kg / cm2

Ps = Suction pressure gauge reading, mm of Hg

3. INPUT POWER:

Pi = (3600 ´ N) / (E´ T) (kw)

Where, Nr = Number of revolutions of energy meter disc

Ne = Energy meter constant (rev / Kw hr)

te = Time taken for ‘Nr’ revolutions (seconds)

4. OUTPUT POWER:

Po = W ´ Qact ´ H /1000 (watts)

Where, W = Specific weight of oil (N / m³)

Qact = Actual discharge (m³ / s)

h = Total head of oil (m)

5. EFFICIENCY:

%h = (Output power Po / input power Pi) ´ 100

DESCRIPTION

Although the gear pump (which consists of two gears), is a rotating machine, yet its

action on liquid to be pumped is not dynamic and it merely displaces the liquid from one side to

the other. Hence, this type of pump comes under positive displacement pumps. The following

diagram illustrates the working principle of a gear pump.

From the above Fig., it seems that, on suction side, the liquid fills up the gaps between the

meshing gears. This liquid, then after passing round the casing, finds its way to pressure side,

when the gears rotate. On the pressure side, the two streams come again together. The major

portion is pushed towards delivery side and a small volume returns back to suction side. The

separation of suction side from delivery side occurs through the flanks of meshing teeth and the

outside casing of the pump, which should have very small clearance with the gears. Since more

than one tooth of each gear may mesh with one another, in between suction and delivery side, a

sort of closed space is formed. The volume of liquid in these closed space changes during rotation

and reaches a certain minimum (i.e., zero when no play). Hence, an arrangement should be

provided such that the entrapped liquid should be able to move out and this is achieved through

sidewalls of pump.

Normally gear pumps are expected to work against small heads of a few atmospheres. High

speed pumps can produce a suction of about 7m. This type of pump is widely used for cooling

water and pressure oil to be supplied for lubrication to motors, turbines, machine tools, and other

similar situations.

PROCEDURE:

1. The gear oil pump is stated.

2. The delivery gauge reading is adjusted for the required value.

3. The corresponding suction gauge reading is noted.

4. The time taken for ‘N’ revolutions in the energy meter is noted with the help of a

stopwatch.

5. The time taken for ‘h’ rise in oil level is also noted down after closing the gate valve.

6. With the help of the meter scale the distance between the suction and delivery gauge

is noted.

7. For calculating the area of the collecting tank its dimensions are noted down.

8. The experiment is repeated for different delivery gauge readings.

9. Finally the readings are tabulated.

Ob

serv

atio

ns

Len

gth

of o

il c

olle

ctin

g ta

nk =

L

=m

,

brea

dth

of o

il c

olle

ctin

g ta

nk =

B

= m

P

lan

area

of

tank

= A

=

LxB

=m

2

Ene

rgy

met

er c

onst

ant =

K

=re

v/kw

h

Dis

tanc

e be

twee

n th

e su

ctio

n an

d de

live

ry g

auge

s =

Dat

um h

ead

= Z

= m

Tab

ula

tion

s

Exp

erim

enta

l dat

a pe

rtai

ning

to g

ear

oil p

ump

wit

h lu

be o

il 4

0 S

AE

:

h %

Ou

tpu

t p

ower

Po

Kw

Mea

n =

Inp

ut

pow

er

Pi

Kw

Tim

e ta

ken

for

N

rev

of

ener

gy

met

er d

isc

t

se

c

Act

ual

d

isch

arge

Qac

t

m³/s

Tim

e ta

ken

fo

r 10

cm

of

ris

e of

w

ater

in

tan

k

t sec

Tot

al

hea

d

H

m

Dat

um

h

ead

Z

m

Su

ctio

n

hea

d

Hs

=

Ps

x 0.

0136

m

Del

iver

y h

ead

H

d=

Pd

x12.

5

m

Su

ctio

n

pre

ssu

re

read

ing

Ps

mm

of

Hg

Del

iver

y p

ress

ure

re

adin

g P

d

kgf

/ cm

2

S.

no

PERFORMANCE OF GEAR OIL PUMP THROUGH GRAPH

The operating characteristics of gear pump, showing the relationship of discharge,

power and efficiency are given below:

Maximum efficiency = %

At maximum efficiency,

Discharge = m3/s

Power = kW

& Head = m

GRAPH H O/P h1. Actual discharge Vs Total head


3. Actual discharge Vs Output

Q

RESULT

Maximum efficiency = %

At maximum efficiency,

Discharge = m3/s

Power = kW

& Head = m

CHARACTERISTICS CURVES OF PELTON WHEEL

Exp No: 8

Date:

AIM:

To conduct load test on pelton wheel turbine and to study the characteristics of pelton wheel turbine.

APPARATUS REQUIRED :

1. Venturimeter

2. Stopwatch

3. Tachometer

4. Dead weight

FORMULAE:

1. VENTURIMETER READING:

h = (P1 ~ P2) ´ 10 (m of water) Where, P1, P2 - venturimeter reading in Kg /cm2

2. DISCHARGE: Q = 0.0055 ´ Ö h (m3 / s)

3. BRAKE HORSE POWER:

BHP = (p x D x N x T) / (60 ´75) (hp) Where,

N = Speed of the turbine in (rpm)

D = Effective diameter of brake drum = 0.315 m

T = Torsion in To + T1 – T2 (Kg)

4. INDICATED HORSE POWER: IHP = (1000 ´ Q ´ H) / 75 (hp) Where,

H = Total head (m)

5. PERCENTAGE EFFICIENCY:

%h = (B.H.P / I.H.P x 100) (%)

DESCRIPTION:

An impulse turbine, whether for water, stream, or gas, is one in which the total drop in

pressure of the fluid takes place in one or more stationary nozzles and there is no change in

pressure of the fluid as it flows through the rotating wheel. As there is no pressure variation in flow

over buckets or vanes, the fluid does no fill the passageway between one bucket or vane and the

next. Customarily, the fluid only acts upon a portion of the circumference of the wheel at any

instant.

Several types of hydraulic impulse turbines have been produced in the past, but the only one

that has survived is the Pelton wheel (Refer Fig) so called in honour of Lester.A.Pelton

Fig: Pelton Wheel Installation

(1829-1908). Pelton patented the wheel with buckets having a splitter in the middle and

W.A.Double brought out the ellipsoidal bucket, which is the basis of the modern forms.

Impulse turbines are usually set with the shaft horizontal, and there is usually only one jet on a

wheel. But more commonly, the multi jet arrangement is used with a vertical shaft arrangement.

Pelton wheels are usually installed under high heads, the pressure loss due to setting is small (i.e.,

Z). If any turbine, in order to maintain a constant speed of rotation, it is necessary that the flow rate

be varied in accordance with the load on the machine; and for the impulse wheel, this is done by

varying the size of the jet and is accomplished by varying the position of the needle in the nozzle.

An important feature in attaining high efficiency in an impulse wheel is that the jet be uniform and

with no spreading out of the jet. The rotative speed of an impulse turbine is maintained constant

throughout, with the use of a governor. The Figure shows an impulse runner where the buckets are

bolted to a rim. The faces of buckets are smooth ground. They are made of bronze or steel. The

height and width of the bucket should each be 2.5 to 4 times the jet diameter, otherwise bucket

efficiency will suffer. Under normal operations all water that issues from the nozzle will act upon

the buckets, for whatever water does not act on the first bucket will act on the second bucket and

so on.

Pelton wheels are highly applicable in generating electricity through generators, only

when the static head (as explained earlier) available is very large. These are also adopted in India

(i.e., Pykara dam)

Ob

serv

atio

ns

Dia

met

er o

f in

let o

f pi

pe =

Dia

. of

inle

t of

vent

urim

eter

= d

1 =

m

Dia

met

er o

f th

roat

of

vent

urim

eter

= d

2 =

m

Dia

met

er o

f w

heel

dru

m =

D =

m

Dia

met

er o

f ro

pe u

sed

in d

ead

wei

ght s

yste

m =

d =

m

Ave

rage

spr

ing

wei

ght (

used

in th

e lo

adin

g sy

stem

) =

Ws =

kg

.

Tab

ula

tion

Exp

erim

enta

l dat

a p

erta

inin

g to

th

e gi

ven

Pel

ton

Wh

eel:

h

%

I.H

.P

hp

Mea

n =

B.H

.P

hp

Dis

char

ge

Q

m3 \s

ec

Ten

sion

T Kg

Sp

rin

gB

alan

ce

T2

Kg

Wei

gh

of

han

ger

T1

Kg

Sp

eed

of

turb

ine

N

Rp

m

Wei

ght

of

han

ger

To

Kg

H=

(P

1-P

2)

x 10

m o

f w

ater

Ven

turi

met

er

read

ing

Kg\

cm2 P2

P1

Tot

al

Hea

d

H

m o

f w

ater

Pre

ssu

reG

auge

Rea

din

gH

p

Kg\

cm2

S.n

o

PROCEDURE:

1. The Pelton wheel turbine is started.

2. All the weight in the hanger is removed.

3. The pressure gauge reading is noted down and it is to be maintained constant for

different loads.

4. The venturimeter readings are noted down.

5. The spring balance reading and speed of the turbine are also noted down.

6. A 5Kg load is put on the hanger, similarly all the corresponding readings are

noted down.

7. The experiment is repeated for different loads and the readings are tabulated.

Performance of Pelton WheelBased on the data collected for the given Pelton wheel or turbine, plots are drawn as shown below.

From the graph,


Optimum speed = rpm

Normal discharge = m3/s

Normal speed = rpm

Graph Q O/P h1. Speed Vs Total head

2. Speed Vs Efficiency

3. Speed Vs Output

NRESULTPerformance of the given Pelton Turbine or Wheel:


Optimum speed = rpm


& Normal speed = rpm

CHARACTERISTICS CURVES OF FRANCIS TURBINE

Exp No: 9

Date:

AIM:

To conduct load test on franchis turbine and to study the characteristics of francis turbine.

APPARATUS REQUIRED:

1. Stop watch

2. Tachometer

FORMULAE:

1. VENTURIMETER READING:

h = (P1 - P2) x 10 (m)

Where

P1, P2- venturimeter readings in kg / cm2

2. DISCHARGE:

Q = 0.011 x Ö h (m3 / s)

3. BRAKE HORSEPOWER:

BHP = p x D x N x T / 60 x 75 (h p)

Where

N = Speed of turbine in (rpm)

D = Effective diameter of brake drum = 0.315m

T = torsion in [kg]

4. INDICATED HORSEPOWER:

HP = 1000 x Q x H / 75 (hp)

Where

H – total head in (m)

5. PERCENTAGE EFFICIENCY:

%h = B.H.P x 100 / I.H.P ( %)

DESCRIPTION:

A reaction turbine is one in which the major portion of pressure drop takes place in the

rotating wheel. As a consequence the proportions must be such that the fluid fills all the runner

passages completely. This makes it necessary that the fluid be admitted to the rotor around its

entire circumference. Since the entire circumference of the reaction turbine is in action, its rotor

need not be as large as that of an impulse wheel for the same power.

The first reaction turbine known is the steam turbine of Hero in Egypt about 120 B.C.

In the hydraulic field the rotating lawn sprinkler is an elementary reaction turbine. The first to be

well-designed inward flow turbine was built in 1849 by eminent hydraulic engineer James

B.Francis. The design of the Francis turbine is shown in Fig (also known as mixed flow runner or

Francis runner). In this runner, all flow lines have both axial and radial components throughout.

Guide Vane Assembly Francis Turbine Installation with Straight

Conical Draft Tube

Francis runner is surrounded by pivoted guide vanes (i.e., the assembly is known as

wicket gates) (Ref. Fig.1). The water is greatly accelerated in guide vanes passages and given a

definite tangential velocity component as it enters the runner. The governor regulates the flow rates

by rotating these vanes about their pivots so that the variation of area occurs between them. The

value of velocity however, is not much affected by the change in the guide vane angle.

Schematic of Various Heads on Reaction Turbine

The water rotates as a free vortex in the space between the ends of the guide vanes and the

entrance edges of the turbine runner. The guide vanes assembly is surrounded in turn by a spiral

case or scroll case, which maintains an uniform velocity around the turbine circumference.

Majority of Francis turbines are set with vertical shafts and the greatest advantage from it is that

the draft tube is then more efficient.

The draft tube is an integral part of a reaction turbine and it has two important functions.

One is to enable the turbine to be set above the tail water level without losing any head thereby.

The second function is to reduce the head loss at submerged discharge and thereby increase the net

head available to the turbine runner. This is accomplished by using a gradually diverting tube.

\ Cavitation phenomenon (when a liquid flows into a region where its pressure is reduced

to vapor pressure, it boils and vapor pockets develop in it) is undesirable because it RESULTs in

pitting of material, mechanical vibrations and loss of efficiency in turbines. In reaction turbines the

most likely place for the occurrence of cavitation is on the backsides of the runner blades near their

trailing edges. Cavitation may be avoided by designing, installing and operating a turbine in such a

manner that at no point that the local absolute pressure drop to the vapor pressure of water. The

most critical factor in the installation of reaction turbines is the vertical distance from the runner to

the tail water.

Ob

serv

atio

ns

Dia

met

er o

f in

let o

f pi

pe =

Dia

. of

inle

t of

vent

urim

eter

= d

1 =

m

Dia

met

er o

f th

roat

of

vent

urim

eter

= d

2 =

m

Dia

met

er o

f w

heel

dru

m =

D =

m

Dia

met

er o

f ro

pe u

sed

in d

ead

wei

ght s

yste

m =

d =

m

Ave

rage

spr

ing

wei

ght (

used

in th

e lo

adin

g sy

stem

) =

Ws =

kg

.

Tab

ula

tion

Exp

erim

enta

l dat

a p

erta

inin

g to

th

e gi

ven

Fra

nci

s T

urb

ine:

h

%

I.H

.P

hp

B.H

.P

hp

Dis

cha

rge

Q

m3 \s

ec

Ten

sion

T Kg

Sp

rin

gB

alan

ce

T2

Kg

Wei

gh

of

han

ger T1

kg

Sp

eed

of

tu

rbin

e

N

Rp

m

Wei

ght

of

han

ger

To

Kg

H=

(P

1-P

2) x

10 m o

f w

ater

Ven

turi

met

er

read

ing

Kg\

cm2 P2

P1

Tot

al

Hea

d

[H]

m o

f H

2O

Pre

ssu

reG

auge

Rea

din

g[H

p]

Kg\

cm2

Mea

n

h

S. n

o

PROCEDURE:

1. The Francis turbine is started

2. All the weights in the hanger are removed

3. The pressure gauge reading is noted down and this is to be maintained constant for

different loads

4. Pressure gauge reading is assended down

5. The venturimeter reading and speed of turbine are noted down

6. The experiment is repeated for different loads and the reading are tabulated.

PERFORMANCE OF FRANCIS TURBINEBased on the data collected for the given Francis turbine, plots are drawn as shown below.

From the graph,


Optimum speed = rpm


Normal speed = rpm

GRAPHQ O/P h

1. Speed Vs Actual Discharge

2. Speed Vs Efficiency

3. Speed Vs Output

N

RESULT

Performance of the given Francis turbine or Runner:


Optimum speed = rpm



KAPLAN TURBINE TEST RIGExp No: 10

Date:

AIM:

To study the characteristics of a Kaplan turbine

DESCRIPTION:

A reaction turbine is one in which the major portion of pressure drop takes place in the

rotating wheel. As a consequence the proportions must be such that the fluid fills all the runner

passages completely. This makes it necessary that the fluid be admitted to the rotor around its

entire circumference. Since the entire circumference of the reaction turbine is in action, its rotor

need not be as large as that of an impulse wheel for the same power.

The first reaction turbine known is the steam turbine of Hero in Egypt about 120 B.C.

In the hydraulic field the rotating lawn sprinkler is an elementary reaction turbine. The first to be

well-designed inward flow turbine was built in 1849 by eminent hydraulic engineer James

B.Francis. The design of the Kaplan turbine is shown in figure 1 (also known as mixed flow runner

or Kaplan runner). In this runner, all flow lines have both axial and radial components throughout.

Kaplan runner is surrounded by pivoted guide vanes (i.e., the assembly is known as wicket

gates) (Ref. Figure.). The water is greatly accelerated in guide vanes passages and given a definite

tangential velocity component as it enters the runner. The governor regulates the flow rates by

rotating these vanes about their pivots so that the variation of area occurs between them. The value

of velocity however, is not much affected by the change in the guide vane angle.

The water rotates as a free vortex in the space between the ends of the guide vanes and

the entrance edges of the turbine runner. The guide vanes assembly, is surrounded in turn by a

spiral case or scroll case which maintains an uniform velocity around the turbine circumference.

Majority of Kaplan turbines are set with vertical shafts and the greatest advantage from it is that

the draft tube is then more efficient.

The draft tube is an integral part of a reaction turbine and it has two important functions. One is to

enable the turbine to be set above the tail water level without losing any head thereby. The second

function is to reduce the head loss at submerged discharge and thereby increase the net head

available to the turbine runner. This is accomplished by using a gradually diverting tube.

Kaplan Turbine Installation with an Elbow Type Draft Tube

Schematic of Various Heads on Reaction Turbine

Cavitation phenomenon (when a liquid flows into a region where its pressure is reduced

to vapor pressure, it boils and vapor pockets develop in it) is undesirable because it RESULTs in

pitting of material, mechanical vibrations and loss of efficiency in turbines. In reaction turbines the

most likely place for the occurrence of Cavitation is on the backsides of the runner blades near

their trailing edges. Cavitation may be avoided by designing, installing and operating a turbine in

such a manner that at no point that the local absolute pressure drop to the vapor pressure of water.

The most critical factor in the installation of reaction turbines is the vertical distance from the

runner to the tail water.

EXPERIMENTAL PROCEDURE:

1. Keep the runner vane at require opening

2. Keep the guide vanes at required opening

3. Prime the pump if necessary

4. Close the main sluice valve and them start the pump.

5. Open the sluice valve for the required discharge when the pump motor switches from

star to delta mode.

6. Load the turbine by adding weights in the weight hanger. Open the brake drum cooling

water gate valve for cooling the brake drum.

7. Measure the turbine rpm with tachometer

8. Note the pressure gauge and vacum gauge readings

9. Note the orifice meter pressure readings.

Repeat the experiments for other loads

Ob

serv

atio

nD

iam

eter

of

inle

t of

pipe

= D

ia. o

f in

let o

f ve

ntur

imet

er =

d1 =

m

Dia

met

er o

f th

roat

of

vent

urim

eter

= d

2 =

m

Dia

met

er o

f w

heel

dru

m =

D =

m

Dia

met

er o

f ro

pe u

sed

in d

ead

wei

ght s

yste

m =

d =

m

Ave

rage

spr

ing

wei

ght (

used

in th

e lo

adin

g sy

stem

) =

Ws =

kg.

Tab

ula

tion

Exp

erim

enta

l dat

a p

erta

inin

g to

th

e gi

ven

Kap

lan

Tu

rbin

e:

h

%

I.H

.P

hp

Mea

n h

B.H

.P

hp

Dis

cha

rge

Q

m3 \s

ec

Ten

sio

n T Kg

Sp

rin

gB

alan

ce

T2

Kg

Wei

gh

of

han

ger T1

kg

Sp

eed

of

tu

rbin

e

N

Rp

m

Wei

ght

of

han

ger

To

Kg

H=

(P

1-P

2)

x 10

m o

f w

ater

Ven

turi

met

er

read

ing

Kg\

cm2 P

2P

1

Tot

al

Hea

d

[H]

m o

f H

2O

Pre

ssu

reG

auge

Rea

din

g[H

p]

Kg\

cm2

S.

no

PERFORMANCE OF KAPLAN TURBINE BY GRAPH

Based on the data collected for the given Kaplan turbine, plots are drawn as shown below.

From the graph,


Optimum speed = rpm


Normal speed = rpm

GRAPH

1. Speed Vs Actual Discharge

2. Speed Vs Efficiency Q O/P h

3. Speed Vs Output

N

RESULT

Performance of the given Kaplan turbine or Runner:


Optimum speed = rpm



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