fm lab manual
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FM Lab Manual : B.E Mechanical Engineering 5th Semester VTU BelgaumTRANSCRIPT
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DEPARTMENT OF MECHANICAL ENGINEERING Fluid Machinery Laboratory Manual
HKBK COLLEGE OF ENGINEERING,BENGALURU Page 1 of 61
EXPERIMENT No.1
VENTURIMETER
Aim: To determine the coefficient of discharge and calibrate the given Venturimeter
for different flow rates
Apparatus: Venturimeter experimental setup, stopwatch, scale
Theory: Write the theory on following topics
i. Statement of Bernoullis Equation
ii. Assumptions for Bernoullis equation
iii. Bernoullis Equation applications
iv. Venturimeter construction and working principle
v. Necessity of divergent portion in Venturimeter
vi. Derivation of discharge through Venturimeter
PUMP MOTOR
Manometer
STORAGE TANK
Measuring Tank
Gate valve
VENTURIMETER
Flow
VENTURIMETER EXPERIMENTAL SETUP
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DEPARTMENT OF MECHANICAL ENGINEERING Fluid Machinery Laboratory Manual
HKBK COLLEGE OF ENGINEERING,BENGALURU Page 2 of 61
Procedure:
1. Fill the sump with clean water to the full level
2. Connect the flexible pipe to the selected pipe line by using quick action coupling
3. Connect the differential manometer to the selected tapping of the Venturimeter
4. Keep the valve open and switch on the pump
5. Keep the bypass valve fully open and the other valves are closed
6. Set a flow rate and wait for a steady state condition
7. Note down the difference in mercury level of differential Manometer
8. Record the time taken to collect R m of water in the measuring tank
9. Repeat the above procedure for different flow rates
Specifications:
Diameter of the pipe, d1=---------------mm
Throat diameter, d2= --------------------mm
Tabular column:
Sl.
No.
x
m of
Hg
h
m of
water
R
m
T
s
Qth
m3/s
Qact
m3/s
Cd %
Error
V
m/s
Re
Where
x= Difference in mercury level of manometer, m of Hg
h= Difference in pressure head in manometer, m of water
= xS
S
l
h 1
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DEPARTMENT OF MECHANICAL ENGINEERING Fluid Machinery Laboratory Manual
HKBK COLLEGE OF ENGINEERING,BENGALURU Page 3 of 61
Sh= Specific gravity of Mercury (heavier liquid)=13.6
Sl= Specific gravity of Water (lighter Liquid)=1
h= x6.12
R= Rise of water in Measuring tank, m
T= Time taken to collect R m of water in measuring tank, s
Qth= Theoretical discharge , m3/s
=2
2
2
1
21 2
aa
ghaa
1a =Area of the pipe or venturimeter inlet, m2
=4
2
1d
1d =Diameter of the pipe or venturimeter inlet, m
2a =Area of throat, m2
=4
2
2d
2d = Diameter of the throat, m
Qact= Actual disharge m3/s
=T
RA
Cd= Coefficient of discharge
=th
act
Q
Q
% Error = 100act
actth
Q
QQ
V=Velocity of water in m/s
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DEPARTMENT OF MECHANICAL ENGINEERING Fluid Machinery Laboratory Manual
HKBK COLLEGE OF ENGINEERING,BENGALURU Page 4 of 61
=1a
Qact
Re=Reynolds Number=1Vd = Density of water, 1000kg/m
3
= Absolute viscosity of water, 1x10-3
Ns/m2
Graphs:
i.Qact v/s h
ii. Qact v/s h
iii. Cd v/s Re
Result:
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DEPARTMENT OF MECHANICAL ENGINEERING Fluid Machinery Laboratory Manual
HKBK COLLEGE OF ENGINEERING,BENGALURU Page 5 of 61
EXPERIMENT NO.2
ORIFICEMETER
Aim: To determine the coefficient of discharge and calibrate the given Orificemeter
for different flow rates
Apparatus: Orificemeter experimental setup, stopwatch, scale
Theory: Write the theory on following topics
i. Construction and working of Orificemeter
ii. Advantages and disadvantages of Orificemeter
ORIFICEMETER
PUMP MOTOR
Manometer
STORAGE TANK
Measuring Tank
Gate valve
ORIFICEMETER EXPERIMENTAL SETUP
Procedure:
1. Fill the sump with clean water to the full level
2. Connect the flexible pipe to the selected pipe line by using quick action coupling
3. Connect the differential manometer to the selected tapping of the Orificemeter
4. Keep the valve open and switch on the pump
5. Keep the bypass valve fully open and the other valves are closed
6. Set a flow rate and wait for a steady state condition
7. Note down the difference in mercury level of differential Manometer
8. Record the time taken to collect R m of water in the measuring tank
9. Repeat the above procedure for different flow rates
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DEPARTMENT OF MECHANICAL ENGINEERING Fluid Machinery Laboratory Manual
HKBK COLLEGE OF ENGINEERING,BENGALURU Page 6 of 61
Specifications:
Diameter of the pipe, d1=---------mm
Orifice diameter, d2= -------------mm
Tabular column:
Sl.
No.
x
m of
Hg
h
m of
water
R
m
T
s
Qth
m3/s
Qact
m3/s
Cd %
Error
V
m/s
Re
Where
x= Difference in mercury level of manometer, m of Hg
h= Difference in pressure head in manometer, m of water
= xS
S
l
h 1
Sh= Specific gravity of Mercury (heavier liquid)=13.6
Sl= Specific gravity of Water (lighter Liquid)=1
h= x6.12
R= Rise of water in Measuring tank, m
T= Time taken to collect R m of water in measuring tank, s
Qth= Theoretical discharge, m3/s
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DEPARTMENT OF MECHANICAL ENGINEERING Fluid Machinery Laboratory Manual
HKBK COLLEGE OF ENGINEERING,BENGALURU Page 7 of 61
=2
2
2
1
21 2
aa
ghaa
1a =Area of the pipe or inlet area of Orifice meter, m2
=4
2
1d
1d =Diameter of the pipe or Orificemeter inlet, m
2a =Area of orifice, m2
=4
2
2d
2d = Diameter of the orifice, m
Qact= Actual discharge m3/s
=T
RA
A= Area of the measuring tank, m2
=lxb
l= Length of the tank, m
b=Breadth of the tank, m
Cd= Coefficient of discharge
=th
act
Q
Q
% Error = 100act
actth
Q
QQ
V=Velocity of water in m/s
=1a
Qact
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DEPARTMENT OF MECHANICAL ENGINEERING Fluid Machinery Laboratory Manual
HKBK COLLEGE OF ENGINEERING,BENGALURU Page 8 of 61
Re=Reynolds Number=1Vd
= Density of water, 1000kg/m3
= Absolute viscosity of water, 1x10-3
Ns/m2
Graphs:
i.Qact v/s h
ii. Qact v/s h
iii. Cd v/s Re
Result:
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DEPARTMENT OF MECHANICAL ENGINEERING Fluid Machinery Laboratory Manual
HKBK COLLEGE OF ENGINEERING,BENGALURU Page 9 of 61
EXPERIMENT No.3
FRICTION IN PIPES
Aim: To determine the coefficient of friction of a given pipe
Apparatus: Friction pipe experimental setup, stop watch, measuring tape
Theory: Write theory on following topics
i. Definition of friction coefficient
ii. Darcys Weichbech and Chezys Formulae and their description
iii. Wet area
iv. Hydraulic mean depth
Procedure:
1. Note down the diameter and length of the pipe
2. Fill the sump with clean water to the full level
3. Connect the manometer limbs between the tapings of the pipe
4. Start the pump and set the flow rate using control valve
5. Note down the difference in manometer
6. Note down the time taken for R rise of water
7. Repeat the experiment for different flow rates
Specifications:
Inner diameter of the pipe d= 1inch=25.4mm for pipe 1
=3/4inch =18mm
=1/2inch=12.5mm
Length of the pipe L=1.5m for all three pipes
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DEPARTMENT OF MECHANICAL ENGINEERING Fluid Machinery Laboratory Manual
HKBK COLLEGE OF ENGINEERING,BENGALURU Page 10 of 61
Tabular column:
Sl.
No.
x
m of Hg
h
m of
water
R
m
T
s
Qact
m3/s
V
m/s
f Re Type of
flow
Where
x= Difference in mercury level of manometer, m of Hg
h= Difference in pressure head in manometer, m of water
= xS
S
l
h 1
Sh= Specific gravity of Mercury (heavier liquid) =13.6
Sl= Specific gravity of Water (lighter Liquid) =1
h= x6.12
R= Rise of water in Measuring tank, m
T= Time taken to collect R m of water in measuring tank, s
Qact =Actual discharge m3/S
=T
RA
A= Area of the measuring tank, m2
= l x b
l= Length of the tank, m
b=Breadth of the tank, m
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DEPARTMENT OF MECHANICAL ENGINEERING Fluid Machinery Laboratory Manual
HKBK COLLEGE OF ENGINEERING,BENGALURU Page 11 of 61
V= Velocity of water in the pipe, m/s
f= Friction coefficient
=24
2
LV
gh
L= Length of the pipe, m
Re=Reynolds Number=Vd
= Density of water, 1000kg/m3
= Absolute viscosity of water, 1x10-3
Ns/m2
Type of flow:
i. Laminar flow -----Re>2000
ii. Transition flow-----Re between 3000 and 4000
iii. Turbulent flow------Re>4000
Result:
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DEPARTMENT OF MECHANICAL ENGINEERING Fluid Machinery Laboratory Manual
HKBK COLLEGE OF ENGINEERING,BENGALURU Page 12 of 61
EXPERIMENT No.4
MAJOR AND MINOR ENERGY LOSSES
Aim: To determine the major and minor energy losses of a flow through a pipe with
different pipe fittings.
Apparatus: Major and minor energy losses experimental setup, stop watch,
measuring tape
Theory: Write theory on following topics
i. Classification of energy losses in a pipe
ii. Definition of major and minor energy losses
iii. Determination of major energy losses theoretically
iv. Determination of minor energy losses( theoretical formulae used)
v. Equivalent length of a pipe
vi. Definition of TEL and HGL and their significance
Procedure:
1. Fill the sump with clean water to the full level
2. Keep the bypass valve fully open and the other valves closed
3. Start the pump and adjust the flow rate to some value
4. Select the fitting for which the pressure drop is to be determined and connect the
manometer across that fitting by opening the corresponding cocks
5. Remove the air bubbles in the manometer
6. Note down the mercury level difference in manometer
7. Note down the mercury level difference in manometer by connecting it to other
fittings
8. Repeat the experiment for different flow rate
Specifications:
i. Diameter of pipe with uniform cross section=27mm
ii. Dimensions of measuring tank=600mmx500mmx250mm
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DEPARTMENT OF MECHANICAL ENGINEERING Fluid Machinery Laboratory Manual
HKBK COLLEGE OF ENGINEERING,BENGALURU Page 13 of 61
Tabular columns:
Type of pipe fittings x, m of Hg h, m of water
Converging collar
Diverging collar
Plain collar
Union
Ball valve
Gate valve
Wheel valve
Non return valve
Pipe length of uniform
cross section
Where
x= Difference in mercury level of manometer, m of Hg
h= Difference in pressure head in manometer, m of water
= xS
S
l
h 1
Sh= Specific gravity of Mercury (heavier liquid) =13.6
Sl= Specific gravity of Water (lighter Liquid) =1
h= x6.12
Result:
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DEPARTMENT OF MECHANICAL ENGINEERING Fluid Machinery Laboratory Manual
HKBK COLLEGE OF ENGINEERING,BENGALURU Page 14 of 61
PUMP MOTOR
Manometer
STORAGE TANK
Measuring Tank
Gate valve
collar
FRICTION IN PIPES AND MAJOR & MINOR ENERGY LOSSES
EXPERIMENTAL SETUP
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DEPARTMENT OF MECHANICAL ENGINEERING Fluid Machinery Laboratory Manual
HKBK COLLEGE OF ENGINEERING,BENGALURU Page 15 of 61
EXPERIMENT No. 5
IMPACT OF JET ON VANES
Aim: To determine the coefficient of impact of a water jet when it strikes different
vanes in fixed condition
Apparatus: Impact of jet on vanes experimental setup, different types of vanes
Theory: Write following theory topics
i. Definition of impact of jet
ii. Principle behind the impact of jet on vanes
iii. Derivation of force applied by a jet on fixed flat plate, inclined vane and
Hemispherical vane
PUMP MOTOR
STORAGE TANK
Gate valve
Balancing weight
Hemispherical vane
Horizontal Lever arm
weights
IMPACT OF JET ON VANES EXPERIMENTAL SETUP
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DEPARTMENT OF MECHANICAL ENGINEERING Fluid Machinery Laboratory Manual
HKBK COLLEGE OF ENGINEERING,BENGALURU Page 16 of 61
Procedure:
1. Select the required diameter of the jet and vane shape and fix them in position
2. Carefully level the horizontal lever by rotating the knob provided at the top of the
weighing balance to zero in the weighing balance
3. Switch on the pump and adjust the flow control valve to give maximum possible
flow through nozzle
4. Note down the flow rate in rotometer and weighing balance reading
5. Reduce the discharge in steps by adjusting the bypass valve and record the series of
rotometer and weighing balance readings
6. Repeat the above procedure for different shapes of vane
Specifications:
i. Diameter of Nozzle
ii. Angle of inclination for an inclined vane
Tabular column:
Type of vane No. of
trials
R
lpm
Qr
m3/s
Fact
N
V
m/s
Fth
N
Ci
Flat vane 1
2
3
Inclined vane 1
2
3
Hemispherical
vane
1
2
3
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DEPARTMENT OF MECHANICAL ENGINEERING Fluid Machinery Laboratory Manual
HKBK COLLEGE OF ENGINEERING,BENGALURU Page 17 of 61
R= Rotometer reading, lpm
Qr = Discharge through Rotometer, m3/S
= 601000
R
Fact= Actual force exerted by the jet, N
V= Velocity of jet, m/s
=a
Qr
a= Cross sectional area of nozzle, m2
=4
2d
d= Diameter of nozzle, m
Fth= Theoretical force applied by the jet, N
=2aV for flat plate
= 22 sinaV for inclined vane
=22 aV for hemispherical vane
= Density of water= 1000kg/m3
= Angle of inclination, degrees
Ci= Coefficient of impact
= th
act
F
F
Result:
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DEPARTMENT OF MECHANICAL ENGINEERING Fluid Machinery Laboratory Manual
HKBK COLLEGE OF ENGINEERING,BENGALURU Page 18 of 61
EXPERIMENT No.6
PELTON WHEEL TURBINE
Aim: To study the performance of Pelton Wheel turbine under constant speed and
constant head and draw the Main (constant head) and operating (constant speed)
characteristic curves
Apparatus: Pelton wheel experimental setup, stop watch
Theory: Write theory on following topics
i. Layout of hydroelectric power plant with some examples
ii. Definition of gross head, net head, head race, tail race, penstock, surge
tank
iii. Definition of Prime mover, Classification of turbines, Impulse turbine
iv. Neat sketch of Pelton Wheel Turbine
v. Construction and working of Pelton wheel
vi. Turbine efficiencies( hydraulic, mechanical, overall, volumetric)
vii. Define unit quantities and draw unit characteristic curves
viii. Explain main, operating and iso-efficiency curves
PELTON WHEEL EXPERIMENTAL SETUP
TURBINE
SPEAR
FLOW POWER SUPPLY
PUMP
COUPLINGMOTOR
WATER TANK
P1
P2DP
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DEPARTMENT OF MECHANICAL ENGINEERING Fluid Machinery Laboratory Manual
HKBK COLLEGE OF ENGINEERING,BENGALURU Page 19 of 61
SINGLE JET PELTON WHEEL
Procedure:
Constant speed:
1. Remove all the loads on the turbine
2. Switch on the pump starter, allow the pump to pick up full speed and becomes
operational
3. Keep the gate valve opening at the maximum
4. Run the turbine with no load condition at the given speed
5. Apply the load (say 1kg) on brake drum using spring balance. Due to this speed of
the turbine decreases.
6. Get back the original speed of the turbine by adjusting gate valve/ spear
7. Note down spring balance readings, pressure gauge and head over V-notch readings
8. Repeat the steps 5, 6, 7 for different load conditions
9. Make sure that the load is released before switching off the turbine.
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DEPARTMENT OF MECHANICAL ENGINEERING Fluid Machinery Laboratory Manual
HKBK COLLEGE OF ENGINEERING,BENGALURU Page 20 of 61
Constant head:
1. Remove all the loads on the turbine
2. Switch on the pump starter, allow the pump to pick up full speed and becomes
operational
3. Keep the gate valve opening at the maximum
4. Set the pressure gauge to the given head (say 4kgf/cm2) using spear
5. Apply the load on brake drum using spring balance. Due this pressure head
decreases.
6. Adjust the spear until the constant head is obtained
7. Note down spring balance readings, head over V-notch and speed of the turbine
8. Repeat the steps 5, 6, 7 for different load conditions
9. Make sure that the load is released before switching off the turbine.
Tabular column: common for both constant head and constant speed conditions
S.
No.
W
Kgs
Pg
kg/cm2
N
rpm
h
=(P1 P2)x10
m
S
kg
H
m
Q
m3/s
I/P
kW
O/P
kW
Nu Pu o
%
P1 P2 h
Pg= Gauge pressure, kg/cm2
W= Load applied, kg
S=Spring balance reading, kg
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DEPARTMENT OF MECHANICAL ENGINEERING Fluid Machinery Laboratory Manual
HKBK COLLEGE OF ENGINEERING,BENGALURU Page 21 of 61
N= Speed of the turbine or brake drum, rpm
h= Venturimeter Head, m
H= Head on turbine, m of water
=10 Pg +Z
Z=Gauge correction with respect to the centreline of turbine, m
Q= Discharge through the turbine, m3/s
= Cd 2
2
2
1
21 2
aa
ghaa
Cd= Coefficient of discharge of V notch=0.6
= Angle of V-notch=900
I/P= Input power of the turbine, kW
=1000
wQH
w= Specific weight of water=9810N/m3
O/P=Out Power of the turbine, kW
=2 NT/(60x1000)
T=Torque induced, Nm
=2
81.9 bD
SW
Db= Diameter of the brake drum, m = 0.36 m
o= Overall efficiency of the turbine, %
= 100/
/
PI
PO
Ns= Specific speed of the turbine,
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DEPARTMENT OF MECHANICAL ENGINEERING Fluid Machinery Laboratory Manual
HKBK COLLEGE OF ENGINEERING,BENGALURU Page 22 of 61
Unit Speed Nu = N/ H
Unit Power Pu = OP/ H3/2
,Unit Discharge Qu = Q/ H
Graphs Main characteristic curves
i. o v/s N
ii. O/P v/s N
iii. Q v/s N
Operating characteristic curves
i. o v/s H
ii. O/P v/s H
iii. Q v/s H
Result:
UN
IT D
ISC
HA
RG
E
UNIT SPEED Nu
1/4 GATE OPENING
FULL GATE OPENING
3/4 GATE OPENING
1/2 GATE OPENING
UN
IT P
OW
ER
Pu
UNIT SPEED Nu
1/4
1/2
3/4
FULL
NIT
EF
FIC
IEN
CY
?
UNIT SPEED Nu
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DEPARTMENT OF MECHANICAL ENGINEERING Fluid Machinery Laboratory Manual
HKBK COLLEGE OF ENGINEERING,BENGALURU Page 23 of 61
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DEPARTMENT OF MECHANICAL ENGINEERING Fluid Machinery Laboratory Manual
HKBK COLLEGE OF ENGINEERING,BENGALURU Page 24 of 61
EXPERIMENT No.7
FRANCIS TURBINE
Aim: To study the performance of Francis turbine under constant speed and constant
head and draw the Main (constant head) and operating (constant speed) characteristic
curves
Apparatus: Francis experimental setup, stop watch
FRANCIS TURBINE EXPERIMENTAL SETUP
Theory: Write theory on following topics
i. Definition of reaction turbine
ii. Neat sketch of Francis Turbine
iii. Construction and working of Francis turbine
iv. Definition of inward and outward turbines
v. Draft tube, functions, types
vi. Difference between impulse and reaction turbines
vii. Explain main, operating and iso-efficiency curves for Francis turbine
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DEPARTMENT OF MECHANICAL ENGINEERING Fluid Machinery Laboratory Manual
HKBK COLLEGE OF ENGINEERING,BENGALURU Page 25 of 61
Procedure:
Constant speed:
1. Remove all the loads on the turbine
2. Switch on the pump starter, allow the pump to pick up full speed and becomes
operational
3. Keep the gate valve opening at the maximum
4. Run the turbine with no load condition at the given speed
5. Apply electrical load (say 400 W) on alternator. Due to this speed of the turbine
decreases.
6. Get back the original speed of the turbine by adjusting gate valve/ guide wheel
7. Note down readings on pressure gauge, vacuum gauge, time for n revolutions of
energy meter disc and head over V-notch
8. Repeat the steps 5, 6, 7 for different load conditions
9. Make sure that the load is released before switching off the turbine.
Constant head:
1. Remove all the loads on the turbine
2. Switch on the pump starter, allow the pump to pick up full speed and becomes
operational
3. Keep the gate valve opening at the maximum
4. Set the pressure gauge to the given head (say 0.75kgf/cm2) using guide wheel
5. Apply electrical load (say 400 W) on alternator. Due this pressure head decreases.
6. Adjust the guide wheel until the constant head is obtained
7. Note down readings on pressure gauge, vacuum gauge, time for n revolutions of
energy meter disc and head over V-notch
8. Repeat the steps 5, 6, 7 for different load conditions
9. Make sure that the load is released before switching off the turbine.
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DEPARTMENT OF MECHANICAL ENGINEERING Fluid Machinery Laboratory Manual
HKBK COLLEGE OF ENGINEERING,BENGALURU Page 26 of 61
Tabular column: common for both constant head and constant speed conditions
Sl.
No.
W
Kgs
Pg
kg/cm2
Vg
Mm of
Hg
N
rpm
h =(P1 P2)x10
m
S
kg
H
m
Q
m3/s
I/P
kW
O/P
kW
o
%
P1 P2 h
W = load in Kgs
Pg= Gauge pressure, kg/cm2
Vg=Vacuum gauge reading, mm of Hg, Wo = Hanger weight = 1 Kg
N= Speed of the turbine or brake drum, rpm, Rb = Brake Drum diameter = 0.3m
h= Venturimeter head
t= time taken for n revolutions of energy
meter disc
H= Head on turbine, m of water
=10 Pg +0.0136 Vg +Z
Z=Gauge correction with respect to the
centreline of turbine, m
Q= Discharge through the turbine, m3/s
= Cd 2
2
2
1
21 2
aa
ghaa
Cd= Coefficient of discharge of Venturimeter
I/P= Input power of the turbine, kW
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DEPARTMENT OF MECHANICAL ENGINEERING Fluid Machinery Laboratory Manual
HKBK COLLEGE OF ENGINEERING,BENGALURU Page 27 of 61
=1000
wQH
w= Specific weight of water=9810N/m3
O/P=Out Power of the turbine, kW
=2 NT/(1000x60).KW
T = (W-S+Wo) 9.81 Rb.N-m
o= Overall efficiency of the turbine, %
= 100/
/
PI
PO
Graphs:
Main characteristic curves
iv. o v/s N
v. O/P v/s N
vi. Q v/s N
Operating characteristic curves
iv. o v/s H
v. O/P v/s H
vi. Q v/s H
Result:
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DEPARTMENT OF MECHANICAL ENGINEERING Fluid Machinery Laboratory Manual
HKBK COLLEGE OF ENGINEERING,BENGALURU Page 28 of 61
EXPERIMENT No. 8
CENTRIFUGAL PUMP
Aim: To study the performance of Centrifugal Pump and draw the characteristic
curves
Apparatus: Centrifugal experimental setup, stop watch
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DEPARTMENT OF MECHANICAL ENGINEERING Fluid Machinery Laboratory Manual
HKBK COLLEGE OF ENGINEERING,BENGALURU Page 29 of 61
SINGLE STAGE CENTRIFUGAL PUMP
Theory:
Write the following theory topics
i. Neat sketch of centrifugal pump, working principle
ii. Different types of casings
iii. Efficiencies of centrifugal pump
iv. Manometric head, NPSH, total head
v. Priming of centrifugal pump
Procedure:
1. Prime the pump
2. Open the delivery valve fully and start the pump.
3. Note down the values of delivery pressure, suction pressure, speed of pump
4. Note down the time taken to collect R m of water in measuring tank and time for
n revolutions of energy meter disc
5. Change the discharge using delivery valve and once again note down the above
readings
6. Repeat the experiment for different discharges
Tabular column:
Sl.
No.
Pg
kg/cm2
Vg
mm
of Hg
N
rpm
R
m
T
s
t
s
H
m
Q
m3/s
I/P
kW
O/P
kW
%
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DEPARTMENT OF MECHANICAL ENGINEERING Fluid Machinery Laboratory Manual
HKBK COLLEGE OF ENGINEERING,BENGALURU Page 30 of 61
Pg=Delivery pressure, kg/cm2
Vg= Vacuum gauge reading, mm of Hg
N= Speed of the pump, rpm
R= Rise of water in Measuring tank, m
T= Time taken to collect R m of water in measuring tank, s
t= time taken for n revolutions of energy meter disc
H= Total Head of the pump, m of water
=10 Pg +0.0136 Vg
Q =Actual discharge m3/s
=T
RA A= Area of the measuring tank, m
2 =l x b,
l= Length of the tank, m
b=Breadth of the tank, m
I/P=Input Power of the turbine, kW
=m
tk
n3600
n= Number of revolutions of energy
meter disc
k= Energy meter constant
m= Efficiency of motor=0.7
O/P= Output power of the turbine,
kW
=1000
wQH
w= Specific weight of water=9810 N/m3
=Efficiency of pump, %
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DEPARTMENT OF MECHANICAL ENGINEERING Fluid Machinery Laboratory Manual
HKBK COLLEGE OF ENGINEERING,BENGALURU Page 31 of 61
= 100/
/
PI
PO
Graphs:
i. Efficiency v/s H
ii. I/P v/s N
iii. Q v/s H
iv. O/P v/s H
Result:
Operating characteristic curves of a centrifugal pump
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DEPARTMENT OF MECHANICAL ENGINEERING Fluid Machinery Laboratory Manual
HKBK COLLEGE OF ENGINEERING,BENGALURU Page 32 of 61
EXPERIMENT No.09
RECIPROCATING PUMP
Aim: To find the percentage slip and study the performance of Reciprocating Pump
Apparatus: Reciprocating pump experimental setup, stop watch
Theory: Write the following theory topics
i. Neat sketch of reciprocating pump, working principle
ii. Slip, % slip
iii. Air vessels- working and applications
iii. Indicator diagram
Fig : - Double-Action Piston Pump
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DEPARTMENT OF MECHANICAL ENGINEERING Fluid Machinery Laboratory Manual
HKBK COLLEGE OF ENGINEERING,BENGALURU Page 33 of 61
Procedure:
1. Prime the pump
2. Open the delivery valve fully and start the pump.
3. Note down the values of delivery pressure, suction pressure and speed of pump
4. Note down the time taken to collect R m of water in measuring tank and time for
n revolutions of energy meter disc
5. Change the discharge using delivery valve and once again note down the above
readings
6. Repeat the experiment for different discharges
Tabular column:
Sl.
No.
Pg
kg/cm2
Vg
mm
of
Hg
N
Rpm
R
M
T
s
t
s
H
m
Qth
m3/s
Qact
m3/s
S
%
I/P
kW
O/P
kW
%
Where
Pg1=Delivery pressure of water in stage 1, kg/cm2
Pg2= Delivery pressure of water in stage 2, kg/cm2
Vg= Vacuum gauge reading, mm of Hg
N= Speed of the pump, rpm
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DEPARTMENT OF MECHANICAL ENGINEERING Fluid Machinery Laboratory Manual
HKBK COLLEGE OF ENGINEERING,BENGALURU Page 34 of 61
R= Rise of water in Measuring tank, m
T= Time taken to collect R m rise of water in measuring tank, s
t= time taken for n revolutions of energy meter disc
H= Total Head of the pump, m of water
=10 Pg+0.0136 Vg
Qth= 60
NLAc
L=Stroke length of cylinder, m
Ac= Area of the cylinder, m2
=4
2D
D= Diameter of cylinder, m
Qact =Actual discharge m3/s
=T
RA
A= Area of the measuring tank, m2
=lxb
l= Length of the tank, m
b=Breadth of the tank, m
S= Percentage Slip
= 100th
actth
Q
QQ
I/P=Input Power of the turbine, kW
=m
tk
n3600
n= Number of revolutions of energy meter disc
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DEPARTMENT OF MECHANICAL ENGINEERING Fluid Machinery Laboratory Manual
HKBK COLLEGE OF ENGINEERING,BENGALURU Page 35 of 61
k= Energy meter constant
m= Efficiency of motor=0.7
O/P= Output power of the turbine, kW
=1000
wQH
w= Specific weight of water=9810 N/m3
=Efficiency of pump, %
= 100/
/
PI
PO
Graphs:
iii. Efficiency v/s H
iv. Q v/s H
v. O/P v/s H
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DEPARTMENT OF MECHANICAL ENGINEERING Fluid Machinery Laboratory Manual
HKBK COLLEGE OF ENGINEERING,BENGALURU Page 36 of 61
EXPERIMENT NO.10
RECIPROCATING AIR COMPRESSOR
Aim: To conduct a performance test on two stage reciprocating air compressor
Apparatus: Two stage reciprocating air compressor setup, tachometer
Theory: Write the following theory topics
i. Compressed air applications
ii. Working of two stage air compressor
iii. Compressor efficiencies
iv. Methods used to get nearly isothermal compression
ON/OFF RPM
AIRT
1
o
C
MainFirst stage Second stage
Manometer
AIR COOLER
HPLP
COMPRESSOR
OUTLET
TWO STAGE RECIPROCATING COMPRESSOR EXPERIMENTAL SETUP
Procedure:
1. Close the delivery valve
2. Switch on the compressor and leave for some time to attain normal speed
3. When the compressor develops the pressure, adjust the control valve and
maintain a constant delivery pressure
4. Note down the manometer reading, speed of motor and compressor,
intermediate pressure, discharge pressure
5. Repeat the experiment for different discharge pressures
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DEPARTMENT OF MECHANICAL ENGINEERING Fluid Machinery Laboratory Manual
HKBK COLLEGE OF ENGINEERING,BENGALURU Page 37 of 61
Specifications:
i. Diameter of LP Cylinder=mm
ii. Stroke length of LP Cylinder=.mm
iii. Diameter of orifice= .mm
Tabular column:
Sl.
No.
Plp
kgf/cm2
Php
kgf/cm2
N
rpm
hw
m of water
Ha
m of
air
Va
m3/s
Vth
m3/
s
Wiso
kW
v
%
h1 h2 hw
Plp= Delivery pressure of air, kgf/cm2
Php= Pressure of HP cylinder, kgf/cm2
N= Speed, rpm
hw= Manometer reading, m of water
Ha= Head of air, m of air
=a
wwh w = Density of water, 1000kg/m3
, a = Density of air, kg/m3 =a
a
RT
P
Pa= Atmospheric pressure, 1.013 x100 kPa, R= Gas constant =0.287 kJ/kg K for air
Ta= Atmospheric or room temperature, K, Va= Actual volume of air delivered, m3/s,
= aod gHAC 2
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DEPARTMENT OF MECHANICAL ENGINEERING Fluid Machinery Laboratory Manual
HKBK COLLEGE OF ENGINEERING,BENGALURU Page 38 of 61
Cd= Coefficient of Discharge=0.62, Ao= Area of orifice, m2 =
4
2
0d
do= Diameter of orifice, m g= Acceleration due to gravity, 9.81m/s2
Vth= Theoretical Volume of air delivered, m3/s
= (dlp2Llp +dhp
2Lhp )/4
dlp=Diameter of LP Cylinder, m dhp=Diameter of HP Cylinder, m
Llp=Stroke length of LP Cylinder, m Lhp=Stroke length of HP Cylinder, m
Wiso=Isothermal work, kW
=1
1
1
100log
P
PPVP dea
P1= Pa= Atmospheric pressure=1.013x100 kPa
v= Volumetric efficiency, %
v = 100th
a
V
V
Graphs:
i. v v/s Pd
ii. iso v/s Pd
iii. v v/s Nc
iv. Ws v/s Va
Result:
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DEPARTMENT OF MECHANICAL ENGINEERING Fluid Machinery Laboratory Manual
HKBK COLLEGE OF ENGINEERING,BENGALURU Page 39 of 61
EXPERIMENT No. 11 & 12
NOTCHES
[RECTANGULAR & V NOTCH]
Aim: To calibrate the given rectangular &V notch
Apparatus used:
1. V notch I Rectangular notch provided in the channel.
2. Hook gauge to measure the head over the notch.
3. A discharge measuring tank fitted with a piezometer and graduated scale.
4. Stop watch.
Theory: A notch is defined as a sharp edged obstruction over which the flow of liquid
occurs. Notches are used for measuring the rate of flow of liquid from a reservoir,
small channel or tank. Gene rally notches are rectangular, triangular [V notch] or
trapezoidal notch. Triangular notch has advantage of greater accuracy at reduced flow
rate compared with other shapes. The coefficient of contraction will be constant for all
heads. The sheet of water discharged by a notch is called "Nappe" or Vein.
Procedure:
1. Place the notch under test at the end of the approach channel, in the vertical plane,
with the sharp edge on the up-stream side.
2. Record the geometric shape of the notch.
3. Allow the water in the tank till it just passes over the notch [up to the crest level].
4. Stop the water supply and record the level of the water by hook gauge when water
just passes over the notch[h1].
5. Increase the supply of water by operating the valve [say by one revolution]. Then
wait for few seconds till the level of the water flow becomes constant. Record the
reading shown on the hook gauge for the water level [h2].
6. The difference h1-h2 give the head over the notch.
7. Collect the water discharging from the notch in measuring tank and measure the
rise of water level 'R' in the tank for certain period of time '1' sec.
8. Repeat the above the procedure for various discharges by operating regulating
valve.
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DEPARTMENT OF MECHANICAL ENGINEERING Fluid Machinery Laboratory Manual
HKBK COLLEGE OF ENGINEERING,BENGALURU Page 40 of 61
WATER TANK
MEASURINGTANK
HOOK GUAGEDIFFERENT SIZE
OF STONES
Graphs:
V notch 1. H vs. Oa 2. Log H vs. log Oa
Rectangular notch 1. H vs Oa 2. Log H vs log Qa
Specification:
V notch Rectangular notch
1. Angle of V notch 90 Width of the notch, b = 0.26m
2. Measuring tank dimensions, A = 0.25m
Formulae:
1. THEORETICAL DISCHARGE:
Through V Notch, Qt = (8 / 15) g2 tan (/2) H5/2
m3 /
sec
Through Rectangular Notch, Qt = (2 / 3) b g2 H3/2
m3 / sec
Where, b = width of notch = 100 mm
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DEPARTMENT OF MECHANICAL ENGINEERING Fluid Machinery Laboratory Manual
HKBK COLLEGE OF ENGINEERING,BENGALURU Page 41 of 61
2. ACTUAL DISCHARGE
Through V-notch & Rectangular notch,Qa = (A * R) / (t)
3. CO-EFFICIENT OF DISCHARGE
Cd = (Actual Discharge) / (Theoretical Discharge)
Tabular column NOTCHES [V NOTCH]
Sl No.
Gauge Reading
(cm)
Head, over
notch,
H = h1 h2
(m)
Time taken
for R m
rise of water
(sec)
Actual. Discharge
Qact
m/s
Theoritical. Discharge
Qth
m/s
Cd Log
Qact
Log
H
h1 h2
1.
2.
3.
4.
5.
6.
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DEPARTMENT OF MECHANICAL ENGINEERING Fluid Machinery Laboratory Manual
HKBK COLLEGE OF ENGINEERING,BENGALURU Page 42 of 61
Tabular column NOTCHES [RECTANGULAR]
Sl No.
Gauge Reading
(cm)
Head, over
notch,
H = h1 h2
(m)
Time taken
for R m
rise of water
(sec)
Actual. Discharge
Qact
m/s
Theoritical. Discharge
Qth
m/s
Cd Log
Qact
Log
H
h1 h2
1.
2.
3.
4.
5.
6.
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DEPARTMENT OF MECHANICAL ENGINEERING Fluid Machinery Laboratory Manual
HKBK COLLEGE OF ENGINEERING,BENGALURU Page 43 of 61
EXPERIMENT No. 13
AIR BLOWER
Aim: To study the performance of a centrifugal blower.
Apparatus: Centrifugal blower test rig, Motor digital tachometer, Manometer etc,
Theory: Write following theory topics
i. Definition of Air Blower
ii. Principle behind the Blower
iii. Applications of Air Blower
ON / OFF SPEED
CONSOLE
ENERGY
METER
IMPELLER
STATIC HEAD
PITOT TUBE
MAINS
ST
AT
IC H
EA
D
FL
OW
RA
TE
Pr. In
volu
te casing MOTOR
DOOR Opeaning
Casing
Flow Rate
Procedure:
1. Connect the input power for console 3HP , ac supply with neutral and earth.
2. Switch as the mains and observe the light indicators are on beneath the
console
3. Switch on the console mains on.
4. Switch on the instrumentation
5. Keep the inlet and outlet valves fully open.
6. Switch on the starter so that motor speed builds up to the constant Rpm
7. Adjust the gate opening and maintain a static head and notedown the readings
I) Blower speed flow ,ii)Static head iii) Energy meter reading Iv) Casing
presurre distribution
8. Repeat the experiment for different heads
9. Switch off the motor and electrical mains
10. Tabulate the readings and draw the following characterstic curves
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DEPARTMENT OF MECHANICAL ENGINEERING Fluid Machinery Laboratory Manual
HKBK COLLEGE OF ENGINEERING,BENGALURU Page 44 of 61
Sl
no
Blower
speed in
rpm
Time taken for 2
revs of energy
meter disc tsec
Static head rise
hstaic m
Flow diff Head of
pitot tube hf m of
water
Input power
KW
Specifications :
1. Area of the duct = 0.066 m2
2. Diameter of the duct = 300 mm
3. Type of the impeller =forward propeller
4. Maximum speed 2800rpm
5. Motor capacity 5HP
6. Electrical input 3phase, 415volts, 30amp ac supply with neutral and earth
Volume flow rate of
discharge m3/min
Static presurre rise of air
Hstatic (m)
Output power
KW
Overall efficiency
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DEPARTMENT OF MECHANICAL ENGINEERING Fluid Machinery Laboratory Manual
HKBK COLLEGE OF ENGINEERING,BENGALURU Page 45 of 61
Calculations:
1. Input power IP=(n x 3600)/(K x t) KW
Where n = no of revolutions of energy metre disc
K = energy meter constant = --------------rev/KWhr
t = time taken for n revolutions of energy meter disc=..sec
2. Static head of air Hstatic = [(( w / a) 1)(hstatic)] ..m
Where w = Density of water i.e., 1000 Kg/m3
a = Density of air at room temperature =..Kg/m3
hstatic = manometer reading
Hstatic = Head of the air
3. Velocity head or flow head Hf = hf [( w / a) 1]..m
Where
hf = manometer reading
Hf = Head of the air
4. Volume flow rate or discharge Q = CdA g2 Hf
5. Output power = (wQHstatic)/1000
w = specific weight of air
6.Efficiency =(OP/IP)100
Graphs:
Volume flow rate v/s static head
Volume flow rate v/s efficiency
Result:
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DEPARTMENT OF MECHANICAL ENGINEERING Fluid Machinery Laboratory Manual
HKBK COLLEGE OF ENGINEERING,BENGALURU Page 46 of 61
KAPLAN TURBINE TEST RIG
AIM:
1) To study the working principle of Kaplan (reaction) turbine. 2) To understand the functional aspects of various components constituting the
turbine.
To study performance characteristics of turbine at various heads, flow rates and
speeds
INTRODUCTION:
Hydraulic (water) Turbines are the machines, which use the energy of water (Hydro
power) and convert it into Mechanical energy, which is further converted into
electrical energy. Thus the turbine becomes the primover to run the electrical
generators to produce electricity (Hydroelectric power).
The Turbines are classified as impulse & reaction types. In impulse turbine,
the head of water is completely converted into a jet, which exerts the force on the
turbine; it is the pressure of the flowing water, which rotates the runner of the turbine.
Of many types of turbine, the Pelton wheel, most commonly used, falls into the
category of impulse turbine, while the Francis & Kaplan falls into the category of
reaction turbines.
Normally, Pelton wheel (impulse turbine) requires high heads and low
discharge, while the Francis & Kaplan (reaction turbines) require relatively low heads
and high discharge. These corresponding heads and discharges are difficult to create
in laboratory because of the limitation of required head & discharges. Nevertheless,
an attempt has been made to study the performance characteristics within the limited
facility available in the laboratories. Further, understanding various elements
associated with any particular turbine is possible with this kind of facility.
DESCRIPTION:
While the impulse turbine is discussed elsewhere in standard textbooks, Kaplan
turbine (reaction type) which is of present concern consists of main components such
as propeller (runner), scroll casing and draft tube. Between the scroll casing and the
runner, the water turns through right angle into axial direction and passes over the
runner and thus rotating the runner shaft. The runner has four blades, which can be
turned about their own axis so that the angle of inclination may be adjusted while the
turbine is in motion. The runner blade angles can be varied to obtain higher efficiency
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DEPARTMENT OF MECHANICAL ENGINEERING Fluid Machinery Laboratory Manual
HKBK COLLEGE OF ENGINEERING,BENGALURU Page 47 of 61
over wide range of operating conditions. In other words even at part loads, when a
low discharge is flowing over the runner, a high efficiency can be attained in case of
Kaplan turbine. Where as this provision does not exist in Francis & Propeller turbines
where the runner blade angles are fixed and integral with the hub.
The actual experimental setup consist of a centrifugal pump set, turbine unit, sump
tank, arranged in such a way that the whole unit works on recirculating water system.
The centrifugal pump set supplies the water from the sump tank to the turbine through
control valve (Butterfly valve) and passes through and orifice meter connected to a
double column mercury manometer which facilitates to obtain the quantity of water
discharged form the turbine unit. Water after passing through the turbine unit enters
the sump tank through the draft tube.
The loading of the turbine is achieved by electrical dynamometer coupled to
the turbine through a V- Belt drive (V grooved pulley). A set of heaters (electrical
resistance) in steps of 200 Watts each, 10 no. (Total 2Kw) with individual switches
provided for loading the electrical dynamometer (in turn loading the turbine). The
provisions for measurement of turbine speed (digital RPM indicator), head on turbine
(pressure gauge) are built-in on the control panel.
A NOTE ON THE SPECIFICATION OF KAPLAN TURBINE
DATA:
* Maximum head available on turbine = 9 - 12 Mts. (H)
* Maximum flow rate available through runner = 0.05 Mt3 / sec (Q)
= 3000 Litters / Min
* Propeller Diameter = 150 mm (D)
* Number of Propeller Blades = 4 No (adjustable)
* Hub Diameter = 60 mm (d)
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DEPARTMENT OF MECHANICAL ENGINEERING Fluid Machinery Laboratory Manual
HKBK COLLEGE OF ENGINEERING,BENGALURU Page 48 of 61
APPARATUS:
a) Centrifugal pump set, sump tank, turbine, piping system to operate the Turbine on closed circuit water circulating system.
b) Digital RPM indicator, pressure gauge, flow control valve, with suitable electrical dynamometer loading with resistance bank (heaters), switches, fan to decipate
heat form the resistance (heaters) load.
SPECIFICATION:
Supply pump capacity : 7.5 Kw (10 Hp) 3ph, 400V, 50 Hz
Turbine capacity : 2.5 HP (1.87 Kw)
Run away speed : 2500 RPM
Loading : Electrical dynamometer (alternator) belt
driven.
2 kva, single phase, 220V, 10 amps, at 1500
RPM.
Transmission efficiency 90% (0.9),
Generator (Alternator) efficiency 75 % ( 0.75).
Resistance (heater) load bank 200 watts each
10 No
Panel mounting & Instrumentation : Digital voltmeter 0-750 V A.C.
Digital ammeter 0- 20 A A.C.
Digital RPM indicator with sensor
(Situated near the Turbine shaft)
Pressure gauge (Bourdon type)
Pump Starter, switches, indicator lamps &
Main rotary switch.
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DEPARTMENT OF MECHANICAL ENGINEERING Fluid Machinery Laboratory Manual
HKBK COLLEGE OF ENGINEERING,BENGALURU Page 49 of 61
OPERATING PROCEDURE:
1) Install the equipment near a 3 phase 440 volts, 50 Hz, 20 amps power source &water source.
2) Connect the panel to the electrical source & ascertain the direction of the pump is in order (clock wise direction from shaft end) by momentarily starting the pump.
3) Fill filtered clear water into the sump tank &discharge tank upto the flow channel level.
4) Keep the butterfly valve situated above the pump in partially closed position & turbine runner blade in full open position.
5) Start the pump, gradually open / close the butterfly valve so that the turbine achieves sufficient speed to generate 220volts on the panel voltmeter
6) Wait till the speed of the turbine & generated voltage maintained constant. 7) Open all the valves provided on the manometer fully and the valves across the
orifice meter partially to release the air trapped in the manometer and observe
water flowing through the air vent tubes.
8) Close both the air vent valves simultaneously and read the difference of mercury level in the manometer limbs to obtain the discharge.
9) Switch ON the first two electrical load switches and adjust the speed of Turbine to 220V on the panel Voltmeter by adjusting the flow control valve and record the
corresponding Ammeter, Pressure gauge and manometer readings.
10) Continue increasing the load on the Turbine step by step by switching ON the consecutive load switches in sets of two and maintain the panel voltmeter reading
at 220V by adjusting the flow control valve accordingly.
11) Record the relative voltmeter, ammeter, pressure gauge and manometer readings on each step.
12) Bring the Turbine to no load condition by switching OFF the load switches in steps.
13) Change the Turbine Runner position by operating the hand wheel situated at the rear end of the Turbine & repeat the experiment following the steps 10 to 12.
14) After the experiment is over bring the turbine to no load condition & stop the pump.
15) Tabulate all the recorded readings and calculate the output power, input power & efficiency of the Turbine.
Note: Drain all the water from the sump tank, refill the sump tank with fresh clean
water once in a month. When the equipment is not in use for a longer duration drain
all the water from the sump tank and keep it clean & dry.
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DEPARTMENT OF MECHANICAL ENGINEERING Fluid Machinery Laboratory Manual
HKBK COLLEGE OF ENGINEERING,BENGALURU Page 50 of 61
OBSERVATION TABLE
Diameter of pipe =150mm (0.15m)
diameter of orifice = 90mm(0.09m)
Sl
No
Turbine
speed
N rpm
Pr Gauge
reading
P
Kg/cm2
Head
over
turbine
H
meters
Presser
Gauge
reading in
Kg/cm2
Across
Orificemete
r
Load Flow
rate
Q
m3/se
c
Input
power
kW
Brake
power
Bp
kW
Turbine
efficienc
y %
turb
Voltag
e
V
Volts
Curren
t
I
Amps
h1 h2
1
2
3
4
5
6
7
CALCULATIONS:
1) Head on turbine H: H = 10 x P where P is the pressure gauge reading in Kg/cm
2
2) Flow rate of water, Q =Cd k2ghw m3/sec
g = 9.81 m/sec2
Cd = 0.62
K = a1 a2 =6.81x10-3
m2
a12 a2
2
hw = h1-h2
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DEPARTMENT OF MECHANICAL ENGINEERING Fluid Machinery Laboratory Manual
HKBK COLLEGE OF ENGINEERING,BENGALURU Page 51 of 61
3) Input power ( Hydraulic power ) Ip = WQH / 1000 kW where W = 9810 N/m
3
4) Brake power
BP = V x I kW where Gen = 0.75
1000 x Gen
5 ) Turbine efficiency
turb = BP / IP x 100 %
CALCULATIONS:
1. Head on turbine H :
H = 10 x P where P is the pressure gauge reading in Kg/cm2
Cd x a1 x a2
Flow rate of water Q = x 2gh m3/sec
a12 - a2
2
Where g = 9.81 m/sec2
Cd = 0.62
a1 = m2
a2 = m2
hw = (h1 h2) x 10 m
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DEPARTMENT OF MECHANICAL ENGINEERING Fluid Machinery Laboratory Manual
HKBK COLLEGE OF ENGINEERING,BENGALURU Page 52 of 61
2. Input power (Hydraulic power input to Turbine)
Ip = WQH Kw where W = 9810 N/m3
1000
3. Output power
Op = V x I Kw
1000 x gen
4. % Turbine efficiency
turb = Output power x 100
Input power
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DEPARTMENT OF MECHANICAL ENGINEERING Fluid Machinery Laboratory Manual
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MULTI STAGE CENTRIFUGAL PUMP TEST RIG
(2 - STAGE)
AIM:
To conduct performance test and draw characteristic curves on a Multi stage (2
stages) Centrifugal pump test rig.
INTRODUCTION:
A pump may be defined as mechanical device when interposed in a pipe line, converts
the mechanical energy supplied to it from an external source into hydraulic energy,
thus resulting in the flow of liquid from lower potential to higher potential.
The pumps are of major concern to most engineers and technicians. The types of
pumps vary in principle and design. The selection of the pump for any particular
application is to be done by understanding their characteristics. The most commonly
used pumps for domestic, agricultural and industrial are Centrifugal, axial flow,
reciprocating, air jet, and diaphram and turbine pumps. Most of these pumps fall into
the main class namely Rotodynamic, Reciprocating (positive displacement) and Fluid
operated pumps.
THEORY:
The principle of operation of a multi stage centrifugal pump is covered under
Rotodynamic pump category. In this pump, the liquid is made to rotate in a closed
volute chamber. Thus creating the centrifugal action, which gradually builds the
pressure gradient towards outlet resulting in a continuous flow.
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DEPARTMENT OF MECHANICAL ENGINEERING Fluid Machinery Laboratory Manual
HKBK COLLEGE OF ENGINEERING,BENGALURU Page 54 of 61
These pumps are of simple construction can be directly coupled to electric
motor and more suitable for handling clear, semi viscous, as well as turbid
liquids. The hydraulic head per stage at low flow rates is limited and hence
not suitable for high heads, in case of single stage centrifugal pumps. But as
the pump in this case in a multi stage construction the pressure gradually
builds up in successive stages almost equally in each stage. Thus achieving
considerably higher heads. The multi stage centrifugal pump test rig allows
the students to understand and study the various characteristics and pressure
build up pattern in individual stages.
DISCRIPTION:
The multi stage Centrifugal pump test rig mainly consists of:
a) Multi stage Centrifugal pump (2 stages) b) AC Drive motor of suitable capacity coupled to pump by stepped pulley
arrangement .
c) SS sump tank and measuring tank with a piezometer d) G. I. Pipe connections with necessary control valve etc mounted on a neatly
painted M.S. structure. The panel board is equipped with an energy meter
for measurement of power input to the motor, a digital RPM indicator to
indicate the speed of the pump/motor, a Vacuum gauge to measure suction
head, two nos. pressure gauges for measurement of stage & delivery head, a
starter of suitable capacity, indicating lamps and fuse.
SPECIFICATIONS:
Multi stage pump (2stage) with Motor
Sump tank:
MOC: Stainless Steel,
Measuring tank:
MOC: Stainless Steel
Area of cross section: 0.125 m2 (Measuring tank)
Drive Belt Size A-29.
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DEPARTMENT OF MECHANICAL ENGINEERING Fluid Machinery Laboratory Manual
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PROCEDURE:
1. Install the equipment near a 1 phase, 220V, 50 Hz, power source and a 25mm tap size water source.
2. Connect the main power input cable to the power source keeping the switch in off position.
3. Fill clear soft water into the sump tank approx. to its full capacity (little less than its full capacity)
4. Keep the outlet control valve (Gate valve) and Butterfly valve situated at the bottom of the measuring tank fully open.
5. Prime the pump if necessary. 6. Start the pump by switching on the motor. 7. Water starts flowing into the measuring tank and drains into sump tank. 8. Observe the readings indicated on Vacuum gauge, pressure gauge stage1&
delivery head, energy meter and record the same.
9. Close fully the butterfly valve situated at the bottom of the measuring tank and observe the rise in water level in the piezometer record the time taken for 10cm
rise in water level on piezometer with the help of a stop watch. Open the butterfly
valve to drain the water back to sump tank.
10. Vary the flow rate by operating the outlet control valve in clock wise direction to any desired position (in steps) and follow steps 10 & 11.
11. Tabulate all the readings and calculate Input power to the pump, outlet power of pump, discharge, efficiency at each step:
CALCULATIONS:
Basic data / constants: 1kg/cm
2 = 760 mm Hg (10 m of water)
Density of water = 1000 kg / m3
Area of collecting tank = 0.125 m2
Discharge rate Q in m3 / sec Q = A x h
t
where h is height of water collected in measuring tank for a time interval of t sec.
Total head H in mts
H = 10(Delivery Pressure + Vacuum head)
= 10(P + Pv / 760)
where P is pressure in kg / cm2 , Pv is the Vacuum in mm of Hg
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DEPARTMENT OF MECHANICAL ENGINEERING Fluid Machinery Laboratory Manual
HKBK COLLEGE OF ENGINEERING,BENGALURU Page 56 of 61
Power input to motor (kW)
Data: Energy meter constant E.M.C. = 1500 Rev/kW .h
K 60 x 60
I.H.P. = x x m = kW.
E.M.C. t
Where motor = 0.87, (87 %)
Where K is the number of revolutions energy meter disc = 5
t is the time taken in seconds by the Energy Meter for K revolutions
m = motor efficiency 0.70 (70% assumed)
(1hp = 0.736 kW)
(1 kW = 1.36
Output Power ( delivered by the pump)
= W x Q x H kW
1000
Where W is 9810 N/m3
% overall = Out power x 100
Shaft power
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DEPARTMENT OF MECHANICAL ENGINEERING DESIGN LABORATORY MANUAL
HKBK COLLEGE OF ENGINEERING,BENGALURU Page 57 of 61
TABULAR COLUMN:
SL
.
N
O
Vacuu
m
gauge
readin
g
MM
Hg
Delivery Head
in kg / cm2
Time t for 10
cm raise of
water in
measuring
tank
Of area 0.125
m2
Dischar
ge
Q
in m3 /
sec
Total
head
(suction
+deliver
y)
in mts
Input
power
In kW
Out put
power
In kW
Over
all
in %
P1
Stage
1
Delive
ry
Head
1.
2.
3.
4.
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DEPARTMENT OF MECHANICAL ENGINEERING DESIGN LABORATORY MANUAL
HKBK COLLEGE OF ENGINEERING,BENGALURU Page 58 of 61
QUESTION BANK FOR FLOW AND HYDRAULIC MACHINES EXPERIMENTS
1. Define fluid. 2. Differentiate between fluid and solid. 3. Define Specific volume 4. Define Specific gravity. 5. Define Viscosity. 6. Define Compressibility. 7. Define vapour pressure. 8. Define Capillarity. 9. Define Surface tension. 10. Differentiate between Absolute and gauge pressures. 11. Mention two pressure measuring instruments. 12. What is peizometer? 13. How manometers are classified. 14. What is pitot static tube? 15. Write down the units for dynamic and kinematic viscosity. 16. State Newtons law of viscosity. 17. Differentiate between Newtonian and non Newtonian fluid. 18. Differentiate between ideal and real fluid. 19. What is ideal plastic fluid? 20. Define velocity gradient. 21. What is the difference weight density and mass density? 22. What is the difference between dynamic and kinematic viscosity? 23. Differentiate between specific weight and specific volume. 24. Define relative density. 25. What is vacuum pressure? 26. What is absolute zero pressure? 27. Write down the value of atmospheric pressure head in terms of water and Hg. 28. Define steady flow. 29. Define uniform flow. 30. Differentiate between laminar and turbulent flow. 31. How will you classify the flow as laminar and turbulent? 32. Differentiate between compressible and incompressible flow. 33. Differentiate between rotational and irrotational flow. 34. Define stream function. 35. Define velocity potential function. 36. Write down continuity equation for compressible and incompressible fluid. 37. Write down continuity equation in three dimensions. 38. Write down Eulers equation of motion. 39. Write down Bernoullis equation of motion for ideal and real fluid. 40. State the assumptions made in Bernoullis equation of motion. 41. Mention the applications of Bernoullis equation of motion. 42. Mention few discharge measuring devices
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DEPARTMENT OF MECHANICAL ENGINEERING DESIGN LABORATORY MANUAL
HKBK COLLEGE OF ENGINEERING,BENGALURU Page 59 of 61
43. Draw the venturimeter and mention the parts. 44. Why the divergent cone is longer than convergent cone in venturimeter? 45. Compare the merits and demerits of venturimeter with orifice meter. 46. Why Cd value is high in venturimeter than orifice meter? 47. What is the difference between Pitot tube and Pitot static tube? 48. What is orifice plate? 49. What do you mean by vena contracta? 50. Define coefficient of discharge. 51. Define coefficient of velocity. 52. Define coefficient of contraction. 53. State Buckinghams Pi Theorem. 54. What is dimensional homogeneity? 55. What is dimensionless number? 56. Mention the methods for dimensional analysis. 57. Mention few important dimensionless numbers. 58. Mention the type of forces acting in moving fluid. 59. Define Reynolds number. 60. What is the difference between model and prototype? 61. Mention two application of similarity laws 62. Define geometric similarity. 63. Define kinematic similarity. 64. Define dynamic similarity. 65. What is the difference between fluid kinematics and fluid dynamics? 66. Write down Hagen poiseulle's equation 67. Sketch the velocity distribution for laminar flow between parallel plates. 68. Sketch the shear stress distribution for laminar flow between parallel plates 69. Differentiate between Hydraulic Gradient line and Total Energy line. 70. Write down Darcy -weisback's equation. 71. Mention the application of moody diagram. 72. What is the difference between friction factor and coefficient of friction? 73. What do you mean by major energy loss? 74. List down the type of minor energy losses. 75. Define drag force. 76. Define lift force. 77. What are the classifications of turbine 78. Define impulse turbine. 79. Define reaction turbine. 80. Differentiate between impulse and reaction turbine. 81. What is the function of draft tube? 82. Define specific speed of turbine. 83. What are the main parameters in designing a Pelton wheel turbine? 84. What is breaking jet in Pelton wheel turbine? 85. What is the function of casing in Pelton turbine 86. Draw a simple sketch of Pelton wheel bucket. 87. What is the function of surge tank fixed to penstock in Pelton turbine? 88. How the inlet discharge is controlled in Pelton turbine?
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DEPARTMENT OF MECHANICAL ENGINEERING DESIGN LABORATORY MANUAL
HKBK COLLEGE OF ENGINEERING,BENGALURU Page 60 of 61
89. What is water hammer? 90. What do you mean by head race? 91. What do you mean by tail race? 92. What is speed ratio? 93. What is flow ratio? 94. What is the difference between propeller and Kaplan turbine? 95. Mention the parts of Kaplan turbine. 96. Differentiate between inward and outward flow reaction turbine. 97. What is the difference between Francis turbine and Modern Francis turbine? 98. What is the difference between outward and inward flow turbine? 99. What is mixed flow reaction turbine? Give an example. 100. Why draft tube is not required in impulse turbine? 101. How turbines are classified based on head. Give example. 102. How turbines are classified based on flow. Give example 103. How turbines are classified based on working principle. Give example. 104. What does velocity triangle indicates? 105. Draw the velocity triangle for radial flow reaction turbine. 106. Draw the velocity triangle for tangential flow turbine. 107. Mention the type of characteristic curves for turbines. 108. How performance characteristic curves are drawn for turbine. 109. Mention the types of efficiencies calculated for turbine. 110. Define Hydraulic efficiency 111. Define Mechanical efficiency. 112. Define overall efficiency. 113. Define pump. 114. How pumps are classified? 115. Differentiate pump and turbine. 116. Define Rotodynamic pump. 117. Define Positive displacement pump. 118. Differentiate between Rotodynamic and positive displacement pump. 119. Define cavitation in pump. 120. What is the need for priming in pump? 121. Give examples for Rotodynamic pump 122. Give examples for Positive displacement pump. 123. Mention the parts of centrifugal pump. 124. Mention the type of casing used in centrifugal pump. 125. Why the foot valve is fitted with strainer? 126. Why the foot valve is a non return type valve? 127. Differentiate between volute casing and vortex casing. 128. What is the function of volute casing? 129. What is the function of guide vanes? 130. Why the vanes are curved radially backward? 131. What do you mean by relative velocity? 132. What is whirl velocity? 133. What do you mean by absolute velocity? 134. What is the function of impeller?
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DEPARTMENT OF MECHANICAL ENGINEERING DESIGN LABORATORY MANUAL
HKBK COLLEGE OF ENGINEERING,BENGALURU Page 61 of 61
135. Mention the types of impeller used. 136. Mention the types of efficiencies calculated for pump. 137. Define Hydraulic efficiency 138. Define Mechanical efficiency. 139. Define overall efficiency 140. Define specific speed of pump. 141. Mention the type of characteristic curves for pump 142. How performance characteristic curves are drawn for pump. 143. Mention the parts of reciprocating pump. 144. What is the function of air vessel? 145. What is slip of reciprocating pump? 146. What is negative slip? 147. What is the condition for occurrence of negative slip? 148. What does indicator diagram indicates? 149. What is the difference between actual and ideal indicator diagram? 150. Briefly explain Gear pump. 151. Differentiate between internal gear pump and external gear pump. 152. Briefly explain vane pump. 153. What is rotary pump? 154. Draw the velocity triangle for centrifugal pump. 155. Draw the indicator diagram fro reciprocating pump. 156. What is the amount of work saved by air vessel? 157. Mention the merits and demerits of centrifugal pump. 158. Mention the merits and demerits of reciprocating pump. 159. What is separation in reciprocating pump? 160. How separation occurs in reciprocating pump? 161. Write down the equation for loss of head due to acceleration in reciprocating pump.
162. Write down the equation for loss of head due to friction in reciprocating pump. 163. Differentiate single acting and double acting reciprocating pump.