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IMPACT OF FREE JETS Objective: - To determine the coefficient of impact of Jet on different vanes by comparing actual force with theoretical force for different types of vanes. Apparatus: -1.Sstop clock, 2.meter scale, 3.Impact of jet on vane setup Theory: - When the jet of water is directed to hit the vane of any particular shape, the force is exerted by the fluid in the opposite direction of the jet. The amount of force exerted depends on the diameter of the jet, shape of the vane, fluid density and velocity of the jet. It also depends on whether the vane is moving or stationary. At this present set up we are concerned about the force exerted on the stationary vanes. The theoretical value of the force is different for different types of vanes. Formulae for Calculations: - 1). Basic data contents (i). 1kg/cm 2 = 760 mm of Hg (10m of water) (ii). Density of water, ‘’ = 1000 kg/m 3 (iii). Diameters of the jet, 8mm, 5mm and 3.5mm 2). Velocity of the Jet, in m/s V = Q / [1000x 60xA] Where Q Discharge rate, liters/min

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IMPACT OF FREE JETS

Objective: - To determine the coefficient of impact of Jet on different vanes by comparing

actual force with theoretical force for different types of vanes.

Apparatus: -1.Sstop clock,

2.meter scale,

3.Impact of jet on vane setup

Theory: - When the jet of water is directed to hit the vane of any particular shape, the force is

exerted by the fluid in the opposite direction of the jet. The amount of force exerted depends

on the diameter of the jet, shape of the vane, fluid density and velocity of the jet. It also

depends on whether the vane is moving or stationary. At this present set up we are

concerned about the force exerted on the stationary vanes. The theoretical value of the force

is different for different types of vanes.

Formulae for Calculations: -

1). Basic data contents

(i). 1kg/cm2 = 760 mm of Hg (10m of water)

(ii). Density of water, ‘’ = 1000 kg/m3

(iii). Diameters of the jet, 8mm, 5mm and 3.5mm

2). Velocity of the Jet, in m/s

V = Q / [1000x 60xA]

Where Q Discharge rate, liters/min

A Area of the jet, m2

3). Theoretical, Tangential force acting on vane in N

a) For Hemispherical vane

Fthe = 2AV2/g

b) For Flat plate

Fthe = AV2/g

c) For inclined plate

Fthe = 2AV2/g Sin, Where, Angle of jet deflection in ‘degrees’

Density of water, 1000 kg/m3; A Area of the jet, m2

V Velocity of the jet in m/s; g Acceleration due to gravity, m2/s

4). Actual, Tangential force acting on vane in N

Fact = F x g

Where, F Force indicator reading in kgf

g Acceleration due to gravity, m2/s

5). Jet Impact co-efficient

Cd = Fact / Fthe

Procedure:- 1. Fill up the sump tank with clean water,

2. Keep the pump delivery valve closed,

3. Keep the Force indicator reading at minimum (zero),

4. Press the green button of the supply pump starter. The pump picks up full speed

and become operational,

5. Now open the delivery valve slowly

6. At one particular velocity of the jet, note down the pressure gauge reading, force

indicator reading, flow rate/ Discharge of the jet and tabulate the readings

7. Repeat the step no. 6 at different jet velocities and at different diameter jets.

8. After the experiment is over keep delivery valve closed, and switch-OFF the

pump.

Fig: Impact free water jet on a curved vane at the center

Sample Calculations: -

Precautions: - 1.Do not start the pump if the supply voltage is less than 250V,

2. The water in the sump tank should be clean.

3. It is recommended to close delivery valve before starting.

Graphs: -To study Impact force and jet co-efficient plot the following graphs,

i). Theoretical Tangential force, Fthe on X-axis Vs actual Tangential force,

Fact on Y-axis

ii). Theoretical Tangential force, Fthe on X-axis Vs Jet co-efficient, Cd on

Y- axis

Expected Graphs: -

Fthe Vs

Cd

Fthe Vs Fact

Fthe

Result: - 1). The value of the actual force is approximately equal to the value of theoretical force.

2). Value of the average Cd =

Table for Observations and Calculations: -

Table:Sl.

No.

Diameter

of the Jet

in ‘mm’

Type of

the vane

Pressure

gauge

reading, in

Kgf/cm2

Force

indicator

reading, F

in Kgf

Fact

in N

Fthe

in N

Cd= Fact

/Fthe

PELTON WHEEL TURBINE

Objective: - To study the characteristic curves of a Pelton wheel turbine at constant

head condition.

Apparatus:-

1. Stop clock,

2. meter scale,

3. Pelton wheel turbine setup,

4. 3-phase power supply.

Theory: - Pelton wheel is a tangential flow high head impulse turbine. Water from the nozzle

strikes the buckets tangentially to the runner wheel. Total energy of the water at the outlet of

the nozzle is in the form of kinetic energy. The pressure at the inlet and outlet of the Turbine

is atmospheric pressure.

Formulae for Calculations: -

1). Head on Turbine in meters of water, H

H = 10P, Where P is the pressure gauge reading in kg/cm2

2). Flow rate of water through Turbine

Qact = 8/15 x Cd√ 2g tan (θ/2) h5/2

Assuming, Cd = 0.6, g= 9.81m/sec2, θ= 60 and

h Head over the notch in meters

3). Hydraulic input to the Turbine

H.Ppump = wQH/75

Where, w 1000kg/m3;

H Head over the Turbine in meters of water.

4). Brake Horse Power (BHP) of Turbine

B.H.P = [2ΠN(F1-F2)r] / 4500

Where, F1 and F2 Spring balance readings in kgf

r Radius of the brake drum in meters (r = 0.15m)

5). Turbine Efficiency

ηtur = (B.H.P / H.Phyd) x 100

6). Unit quantities under unit head

(a). Unit Speed; Nu = N / √ H

(b). Unit Power; Pu = P / H3/2

( c). Unit discharge; Qu = Q / √ H

7). Specific Speed

Ns = N √ P / H5/4

Procedure:-

1. Fill up the sump tank with clean water,

2. Keep the butterfly valve and sphere valve closed,

3. Keep the brake drum loading at minimum (zero),

4. Press the green button of the supply pump starter. The pump picks up full speed and

become operational,

5. Now keep the butterfly valve opening at minimum,

6. Slowly open the sphere valve so that the Turbine runner picks up the speed and attains the

maximum at full opening of the valve,

7. At one particular head on the Turbine note down the speed, head over notch, brake loads

and tabulate the readings

8. Repeat the step no. 7 at different brake loads and note down the readings of speed

9. After the experiment is over keep sphere valve and butterfly valve closed, and switch-OFF

the pump.

Sample Calculation: -

Precautions:

1.The water in the sump tank should be clean.

2. To start and stop supply pump, keep gate valve closed.

3. It is recommended to close sphere valve before starting.

Graphs:

To study constant head characteristic curves of a Pelton wheel Turbine plot

the following graphs,

i). Unit Speed, Nu on X-axis Vs Unit Power, Pu on Y-axis

ii). Unit Speed, Nu on X-axis Vs Unit discharge, Qu on Y-axis

iii). Unit Speed, Nu on X-axis Vs ηoverall on Y-axis

Result: - 1. The constant head characteristic curves have been obtained

2. The maximum efficiency of the Pelton wheel is =

Table for Observations: -

Sl. No.Runner speed, ‘N’

in RPM

Head over the Turbine,

‘P’ in kgf/cm2

Head over the notch,

‘h’ in meters

Spring balance reading in kgf

F1 F2

Tables for Calculations:

Sl. No.Net Head, H

in meters

Flow rate , Q

in m3/secH.Phyd

B.H

.Pηturbine

Unit

Speed,

Nu

Unit

Power,

Pu

Unit

Discharge

, Qu

Expected Graphs:

Qu Vs Nu

Pu Vs Nu

ηpumpVs Nu

Nu

FRANCIS TURBINE at Constant head condition

Objective: To study the characteristic curves of a Francis turbine at constant head condition.

Apparatus:

1. Stop clock,

2. Meter scale,

3. Francis turbine setup,

4. 3-phase power supply.

Theory: Francis turbine is a reaction turbine operated at medium head. It consists of guide vanes,

runner, scroll casing and draft tube at the exit. Water turns through right angles and guided

through the runner and thus rotating the runner shaft. By varying the guide vane angles, high

efficiency can be maintained over a wide range of operating conditions. After passing

through the turbine, water enters into the collecting tank through draft tube. Loading of the

turbine can be done by brake drum arrangement.

Formulae for Calculations: -

1). Head on Turbine in meters of water, H

H = 10(P + Pv / 760)

Where P pressure gauge reading in kg/cm2

Pv Vacuum pressure gauge reading in mm of Hg

2). Flow rate of water through Turbine

Q = 2/3 x b x Cd√ 2g h3/2

Assuming, Cd = 0.6, g= 9.81m/sec2, b = 0.5m

h Head over the notch in meters

3). Hydraulic input to the Turbine

H.Phyd = wQH/75

Where, w 1000kg/m3;

Q Flow rate of water, in m3/s

H Head over the Turbine in meters of water.

4). Brake Horse Power (BHP) of Turbine

B.H.P = [2ΠN(F1-F2)r] / 4500

Where, F1 and F2 Spring balance readings in kgf

r Radius of the brake drum in meters (r = 0.15m)

5). Turbine Efficiency

ηtur = (B.H.P / H.Phyd) x 100

6). Unit quantities under unit head

(a). Unit Speed; Nu = N / √ H

(b). Unit Power; Pu = P / H3/2

( c). Unit discharge; Qu = Q / √ H

Procedure:-

1. Keep the butterfly valve and gate valve closed,

2. Keep the brake drum loading at minimum (zero),

3. Press the green button of the supply pump starter. The pump picks up full speed and

become operational,

4. Now keep the butterfly valve opening at minimum,

5. Slowly open the gate valve so that the Turbine runner picks up the speed and attains the

maximum at full opening of the valve,

6. At one particular head on the Turbine note down the speed, head over notch, brake loads

and tabulate the readings

7. Repeat the step no. 6 at different brake loads and note down the readings.

8. After the experiment is over keep sphere valve and butterfly valve closed, and switch-

OFF the pump.

Sample Calculation:

Precautions:

1. The water in the sump tank should be clean.

2. To start and stop supply pump, keep gate valve closed.

3. It is recommended to close guide vanes before starting.

Graphs:

To study constant head characteristic curves of a Francis Turbine plot the

following graphs,

i). Unit Speed, Nu on X- axis Vs Unit Power, Pu, on Y- axis

ii). Unit Speed, Nu on X- axis Vs Unit discharge, Qu on Y- axis

iii). Unit Speed, Nu on X- axis Vs ηoverall on Y- axis

Result:

1. The constant head characteristic curves have been obtained

2. The maximum efficiency of the Francis Turbine is =

Table for Observations: -

Sl. No.

Runner

speed, ‘N’ in

RPM

Head over the Turbine Head over the

notch, ‘h’ in

meters

Spring balance reading in kgf

‘P’ in kgf/cm2 Pv in mm of Hg F1 F2

Tables for Calculations: -

Sl. No.

Net Head,

H in

meters

Flow rate,

Q in m3/secH.Phyd B.H.P

ηtur

bine

Unit

Speed

, Nu

Unit

Powe

r, Pu

Unit

Dischar

ge, Qu

Expected Graphs: -

Qu Vs Nu

Pu Vs Nu

ηpumpVs Nu

Nu

04. KAPLAN TURBINE at Constant head condition

Objective: - To study the characteristic curves of a Kaplan turbine at constant head condition.

Apparatus: - stop clock, meter scale, Kaplan turbine setup, 3-phase power supply.

Theory: - Kaplan turbine is a reaction turbine operated at low head. It consists of guide vanes,

runner, scroll casing and draft tube at the exit. Water turns through right angles and guided

through 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 operation. By varying the guide vane angles, high efficiency can be maintained

over a wide range of operating conditions. After passing through the turbine, water enters

into the collecting tank through draft tube. Loading of the turbine can be done by electrical

switches arrangement. (Electrical loading)

Formulae for Calculations: -

1). Head on Turbine in meters of water, H

H = 10(P + Pv / 760)

Where P pressure gauge reading in kg/cm2

Pv Vacuum pressure gauge reading in mm of Hg

2). Flow rate of water through Turbine

Q = 2.95 x L x h3/2

Where, L Crest width in meters (L= 0.5m)

h Head over the notch in meters

3). Hydraulic input to the Turbine

H.Phyd = wQH/75

Where, w 1000kg/m3;

Q Flow rate of water, in m3/s

H Head over the Turbine in meters of water.

4). Electric power as indicated by the energy meter

H.Pelec = (5/1500) x (1000/736) x (60x60)/t = 16.3 / t

Where, t it is the time taken for 5 revolutions of the energy meter in sec.

5). Brake Horse Power (BHP) of Turbine

B.H.P = H.Pelec / ηgenerator

Where, ηgenerator Generator Efficiency (ηgenerator =75%)

5). Turbine Efficiency

ηtur = (B.H.P / H.Phyd) x 100

6). Unit quantities under unit head

(a). Unit Speed; Nu = N / √ H

(b). Unit Power; Pu = P / H3/2

( c). Unit discharge; Qu = Q / √ H

Procedure:- 1. Keep the butterfly valve and gate valve closed,

2. Keep the brake drum loading at minimum (zero),

3. Press the green button of the supply pump starter. The pump picks up full speed and

become operational,

4. Now keep the butterfly valve opening at minimum,

5. Slowly open the gate valve so that the Turbine runner picks up the speed and attains the

maximum at full opening of the valve,

6. At one particular head on the Turbine note down the speed, head over notch, wattage of

electrical load bulbs in action, load on generator, energy meter reading and tabulate the

readings

7. Repeat the step no. 6 at different electrical bulb loads and note down the readings.

8. After the experiment is over keep sphere valve and butterfly valve closed, and switch-

OFF the pump.

Sample Calculation: -

Fig: Sectional arrangement of Kaplan Turbine

Precautions: -1. The water in the sump tank should be clean.

2. To start and stop supply pump, keep gate valve closed.

3. It is recommended to close guide vanes before starting.

Graphs: -To study constant head characteristic curves of a Francis Turbine plot the following

graphs,

i). Unit Speed, Nu on X- axis Vs Unit Power, Pu, on Y- axis

ii). Unit Speed, Nu on X- axis Vs Unit discharge, Qu on Y- axis

iii). Unit Speed, Nu on X- axis Vs ηoverall on Y- axis

Result: - 1. The constant head characteristic curves have been obtained

2. The maximum efficiency of the Kaplan Turbine is =

Table for Observations: -

Table: 1

Sl.

No.

Runner

speed, ‘N’

in RPM

Head over the TurbineHead

over the

notch, ‘h’

in meters

Load on

generatorWattage

of bulbs

in action

Time taken for 5

rev. of Energy

meter reading, ‘t’

sec.

‘P’ in

kgf/cm2

Pv in mm of

Hg

V in

Volts

I in

Amps

Tables for Calculations: -

Table: 2

Sl. No.

Net Head,

H in

meters

Flow rate,

Q in m3/secH.Phyd B.H.P

ηtur

bine

Unit

Speed

, Nu

Unit

Powe

r, Pu

Unit

Dischar

ge, Qu

Expected Graphs: -

Qu Vs Nu

Pu Vs Nu

ηpumpVs Nu

Nu

05. MULTISPEED SINGLESTAGE CENTRIFUGAL PUMP TEST RIG

Objective: - To plat the operational characteristic curves of a Multi-speed single stage centrifugal

pump.

Apparatus:-Multi-speed single stage centrifugal pump test set-up, stop clock, steel rule etc.

Theory:-In general a pump may be defined as a mechanical device which when interposed in a

pipe-line converts mechanical energy supplied to it from some internal source in to

hydraulic energy thus resulting in the flow of liquid from the lower potential/head to the

higher potential/head. Multi-speed Single stage centrifugal pump falls in to the category of

Roto-dynamic pumps. In these pumps the liquid is made to rotate in a closed chamber/casing

thus creating the centrifugal action, which gradually builds the pressure gradient towards

outlet, thus resulting in the continuous flow. Hydraulic head developed by the centrifugal

pump is low hence; it is not suitable for high heads as compared to the reciprocating pumps

of same capacity and stage

Formulae for Calculations: -

1). Basic data contents

(i). 1kg/cm2 = 760 mm of Hg (10m of water)

(ii). Density of water, ‘w’ = 1000 kg/m3

(iii). Energy meter constant = 1500rev/1kWh

(iv). Area of collecting tank, ‘A’ = 0.25m2

2). Discharge rate ‘Q’ in m3/sec

Q=(A x h) / (1000 x T) = 0.25h/1000T

Where, A 0.25m2 , is the area of collecting tank,

h Height of water collected in the collecting tank., in mm

T Time taken in seconds for water collection in sec.

3). Total head ‘H’ in meters

H = 10 x (Delivery pressure + Vacuum head)

H = 10(P + Pv/760)

Where, P Pressure (at stage 4)in kg/cm3,

Pv Vacuum pressure in mm of Hg.

4). Electric power as indicated by the energy meter

H.Pelec = (10 /1500) x (1000/736) x (60x60)/t = 32.61/

Where, t It is the time taken for 10 revolutions of the energy meter in sec.

5). Hydraulic H.P (Delivered by the pump)

H.Ppump = wQH/75

Where, w 1000kg/m3;

H Total/ Manometric head in meters.

6). Pump Efficiency

ηpump = H.Ppump / (H.Pelec x ηmotor) x 100

Where, ηmotor Assumed as 70%;

ηoverall = H.Ppump/H.Pelec x 100

Procedure:-1. Fill the sump tank with clean water,

2. Keep the delivery and suction valves open,

3. Switch on the mains, so that the mains-ON indicator glows. Now switch-ON the pump,

4. Close the delivery valve slightly so that the delivery pressure is readable.

5. Operate the delivery valve to note down the collecting tank reading against the known

time, keep it open when the readings are not taken. Also note down the delivery pressure

and other readings,

6. Repeat the steps 5 for different openings of delivery valve.

7. After the experiment is over keep all the delivery and suction valves open and switch-

OFF the pump.

Sample Calculation: -

Precautions: -1.Do not start the pump if the supply voltage is less than 300V,

2. The water in the sump tank should be clean.

3. Accurate readings must be taken to get the good results.

Graphs: -To analysis the operating characteristic curves of a multi stage centrifugal pump, plot the

following graphs,

i). Discharge, ‘Q’ Vs Manometric Head, ‘H’

ii). Discharge, ‘Q’ Vs Input power,

iii). Discharge, ‘Q’ Vs ηoverall

Result: -1. The operational characteristic curves have been obtained

2. The maximum efficiency of the multi speed single stage centrifugal pump is=______

Table for Observations: -

Table: 1

Sl.

No.

Speed,

N in

RPM

Delivery head

pressure, P in

kg/cm2

Suction head

(Vacuum), Pv in

mm of Hg

Time taken for 10

rev. of Energy

meter reading, ‘t’

sec.

Height of

water

collected,

h in mm

Disch

arge

time

in sec

Table for Calculations: -

Table: 2

Sl.

No.

Head, H in

meters

Rate of discharge in

m3/s

H.Pelec (No

load)H.Ppump

H.Po

verall

ηpump

Expected Graphs: -

H Vs Q

P Vs Q

ηpumpVsQ

Q

06. MULTISTAGE CENTRIFUGAL PUMP TEST RIG.

Objective: - To plat the operational characteristic curves of a multistage centrifugal pump.

Apparatus:-Multistage (4-stage) centrifugal pump test set-up, stop clock, steel rule etc.

Theory:-In general a pump may be defined as a mechanical device which when interposed in a

pipe-line converts mechanical energy supplied to it from some internal source in to

hydraulic energy thus resulting in the flow of liquid from the lower potential/head to the

higher potential/head.

Multistage centrifugal pump falls in to the category of Roto-dynamic pumps. In these

pumps the liquid is made to rotate in a closed chamber/casing thus creating the centrifugal

action, which gradually builds the pressure gradient towards outlet, thus resulting in the

continuous flow. Hydraulic head developed by the centrifugal pump is low hence; it is not

suitable for high heads as compared to the reciprocating pumps of same capacity and stage.

But if the pump is of multistage construction the pressure gradually builds up in successive

stages all most equally in a stage.

Formulae for Calculations: -

1). Basic data contents

(i). 1kg/cm2 = 760 mm of Hg (10m of water)

(ii). Density of water, ‘w’ = 1000 kg/m3

(iii). Energy meter constant = 150rev/1kWh

(iv). Area of collecting tank, ‘A’ = 0.25m2

2). Discharge rate ‘Q’ in m3/sec

Q=(A x h) / (1000 x T) = 0.25h / 1000T

Where, A Area of collecting tank, 0.25 m2

h Height of water collected in the collecting tank., in mm

T Time taken in seconds for water collection in sec.

3). Total head ‘H’ in meters

H = 10 x (Delivery pressure + Vacuum head)

H = 10(P + Pv/760)

Where, P Pressure (at stage 4)in kg/cm3,

Pv Vacuum pressure in mm of Hg.

4). Electric power as indicated by the energy meter

H.Pelec = (10/150) x (1000/736) x (60x60)/t = 32.61 x 10/t

Where, t It is the time taken for 10 revolutions of the energy meter in sec.

5). Hydraulic H.P (Delivered by the pump)

H.Ppump = wQH/75

Where, w 1000kg/m3;

H Total/ Manometric head in meters.

6). Pump Efficiency

ηpump = H.Ppump / (H.Pelec x ηmotor) x 100

Where, ηmotor Assumed as 70%;

ηoverall = H.Ppump/H.Pelec x 100

Procedure:-1. Fill the sump tank with clean water,

2. Keep the delivery and suction valves open,

3. Switch on the mains, so that the mains-ON indicator glows. Now switch-ON the pump,

4. Close the delivery valve slightly so that the delivery pressure is readable.

5. Operate the delivery valve to note down the collecting tank reading against the known

time, keep it open when the readings are not taken.

6. Note down the pressure at each stage and also other readings,

7. Repeat the experiment for different openings of delivery valve.

8. After the experiment is over keep all the delivery and suction valves open and switch-

OFF the pump.

Sample Calculation: -

Precautions: -1.Do not start the pump if the supply voltage is less than 300V,

2. The water in the sump tank should be clean.

3. Accurate readings must be taken to get the good results.

Graphs: -To analysis the operating characteristic curves of a multi stage centrifugal pump, plot the

following graphs,

i). Discharge, ‘Q’ on X-axis Vs Manometric Head, ‘H’ on Y-axis

ii). Discharge, ‘Q’ on X-axis Vs Input power on Y-axis

iii). Discharge, ‘Q’ on X-axis Vs ηoverall on Y-axis

Result: - 1. The operational characteristic curves of centrifugal pump have been obtained

2. The maximum efficiency of the Centrifugal pump is = _________

Table for Observations: -

Table: 1

Sl.

No.

Delivery head pressure,

kg/cm2

Suction

head

(Vacuum),

Pv in mm of

Hg

Time taken for 10

rev. of Energy

meter reading, ‘t’

sec.

Height of

water

collected,

h in mm

Disch

arge

time

in sec

Stage

-I

Stage-

II

Stage-

III

Stage-IV

( P )

Table for Calculations: -

Table: 2Sl.

No.

Head, H in

meters

Rate of discharge in

m3/s

H.Pelec (No

load)H.Ppump ηpump H.Poverall

Expected Graphs: -

H Vs Q

P Vs Q

ηpumpVsQ

Q

07. RECIPROCATING PUMP TEST RIG.

Objective: - To obtain the operational characteristic curves of a Reciprocating pump.

Apparatus:-Reciprocating pump test set-up, stop clock, meter scale etc.

Theory:-In general a pump may be defined as a mechanical device which when interposed in a

pipe-line converts mechanical energy supplied to it from some internal source in to hydraulic

energy thus resulting in the flow of liquid from the lower potential/head to the higher

potential/head.

Reciprocating pump is a positive displacement pump, which is having a plunger

(piston) moves to and fro in a closed cylinder. The cylinder is connected to suction and

delivery pipes and are lifted with non-return valves to admit the liquid in one direction only.

The non-return valve at the suction side, allows the liquid only to enter the cylinder and the

delivery non-return valve allows the liquid only to escape out from the cylinder to the delivery

pipe.

For more uniform flow, an air vessel is fitted before the suction valve, and after

delivery valve. This contributes for more uniform flow of liquid also saves energy input to the

pump from the prime mover.

Formulae for Calculations: -

1). Basic data contents

(i). 1kg/cm2 = 760 mm of Hg (10m of water)

(ii). Density of water, ‘w’ = 1000 kg/m3

(iii). Energy meter constant = 1500rev/1kWh

(iv). Area of collecting tank, ‘A’ = 0.125m2

2). Electric power as indicated by the energy meter

H.Pelec = (5/1500) x (1000/736) x (60x60)/t = 16.3 / t

Where, t it is the time taken for 5 revolutions of the energy meter in sec.

3). Shaft Horse Power as indicated by swinging field dynamometer

H. Pshaft = H.Pelec x ηmotor

Where, ηpump Motor efficiency, 75%

4). Discharge rate ‘Q’ in m3/sec

Q = (A x h) / (1000 x T) = 0.125h/1000T

where, A 0.125m2 , is the area of collecting tank,

h Height of water collected in the collecting tank., in mm

T Time taken in seconds for water collection in sec.

5). Total head ‘H’ in meters

H = 10 x (Delivery pressure + Vacuum head)

H = 10(P + Pv/760)

Where, P Pressure (at stage 4)in kg/cm3,

Pv Vacuum pressure in mm of Hg.

6). Hydraulic H.P (Delivered by the pump)

H.Ppump = wQH/75

Where, w 1000kg/m3;

H Total/ Manometric head in meters.

7). Pump Efficiency

ηpump = H.Ppump / H.Pshaft x 100

8). Overall Efficiency

ηoverall = H.Ppump/ H.Pelec x 100

Procedure: - 1. Fill the sump tank with clean water,

2. Keep the delivery and suction valves open,

3. Set the required speed using the stepped pulley. Switch on the mains, so that the mains-

ON indicator glows.

4. Note down the pressure gauge, vacuum gauge and time for number of revolutions of

energy meter disc at full opening of delivery and suction valves,

5. Operate the butterfly valve to note down the collecting tank reading against the known

time, keep it open when the readings are not taken.

6. Repeat the experiment for different openings of the delivery valve.

7. After the experiment is over keep all the delivery and suction valves open and switch-

OFF the pump.

Sample Calculation: -

Fig Schematic

diagram of

Reciprocating pump

Precautions: -1. The water in the sump tank should be clean.

2. Initially the suction and delivery valves should be kept fully open,

3. Accurate readings must be taken to get the good results.

Graphs: -To study the operating characteristic curves of a Reciprocating pump, plot the following

graphs,

i). Total head, ‘H’ on X-axis Vs Discharge, ‘Q’ on Y-axis

ii). Total head, ‘H’ on X-axis Vs Shaft Input power, on Y-axis

iii). Total head, ‘H’ on X-axis Vs ηpump on Y-axis

Result: - 1. The operational characteristic curves of Reciprocating pump have been obtained

2. The maximum efficiency of the Reciprocating pump is =

Table for Observations: -

Table: 1

Sl.

No.

Pump

Speed,

‘N’ in

RPM

Delivery

head

pressure, P in

kg/cm2

Suction head

(Vacuum), Pv

in mm of Hg

Time taken for 5

rev. of Energy

meter reading, ‘t’

in sec.

Height of

water

collected,

‘h’ in mm

Discharge

time. ‘T’ in

sec

Table for Calculations: -

Table: 2

Sl.

No.

Pump

Speed, ‘N’

in RPM

Total

Head, H in

meters

Rate of

discharge, ‘Q’

in m3/sec

H.Ppum

p

H.Pshaft

H.

Pele

c

ηp

um

p

ηover

all

Expected Graphs: -

Q Vs H

P Vs H

ηpumpVsH

H

08. CALIBRATION OF VENTURI METER

Objective: - - To calibrate venturimeter and to determine the co-efficient of discharge of the given

venturimeter.

Apparatus: -Venturi meter fixed in a pipeline, manometer, collecting tank, stop watch.

Theory: -Venturi meter is a device which is used to measuring the rate of flow of fluid through a

pipeline. The basic principle on which a Venturi meter works is that by reducing the cross

sectional area of the flow passage, a pressure difference is created between the inlet and

throat and the measurement of pressure difference enables the determination of the

discharge through the pipe.

A Venturi meter consists of i). An inlet section followed by a convergent cone

section, ii). A cylindrical throat and iii). A gradually divergent cone section. At the inlet

section and at the throat of the Venturi meter pressure taps are provided through the

pressure rings.

Formulae for Calculations: -

1. Basic data contents

(i). Area of the collecting tank, 0.12 m2

(ii). Diameter of the pipeline, d1 = 25mm,

(iii). Diameter of the throat, d2 = 12.5mm,

2. Theoretical discharge through the pipe line

QThel = A1A2√ 2gH) / √ (A12– A2

2)

Where, H Difference in manometer limb levels, in meters of water;

A1 Cross sectional area of the inlet section of the Venturi, in m2;

A2 Cross sectional area of the Outlet section of the Venturi, in m2;

g Acceleration due to gravity in m/sec2

3. Actual discharge through Venturi meter

Qact= A Lr / T

Where, A Area of the collecting tank in meters;

Lr Height of water collected in the collecting tank., in meters

T Time taken in seconds for water collection in sec

3. Co efficient of discharge, Cd

Cd = Qact / QThe

4. To determine k and n (from calibration curve)

Qact = k (H) n where k is a const and k = Cd A1 A2√ 2g) / √ (A12– A2

2)

log (Qact)= n log (H) + log (k) ( i.e y = mx +c form)

Procedure: -1. Switch on the pump and open the delivery valve

2. Open the corresponding ball valve of the venturimeter pipes

3. Note down the differential head reading in the manometer (expel if any air is trapped by

opening the drain cocks provided with the manometer.)

4. From the known pressure head difference, the ideal discharge is calculated using the

basic formula. The actual discharge is determined by finding time taken for specific

volume of water collection in the collecting tank.

5. Repeat the steps 2 to 4 for different flow rates and note down the readings.

6. After the experiment is over keep supply valve closed, and switch-OFF the pump.

Sample Calculation: -

Precautions: -1.Do not start the pump if the supply voltage is less than 300V,

2. The water in the tank should be clean.

3. See that there should be no water leakage from the Venturi meter connections

Graphs: -To find, co efficient of discharge through graph plot the following graphs

1. Theoretical discharge, Qthe on X-axis Vs Actual discharge, Qact on Y-axis

2. log (Qact) on Y-axis Vs log (H)on X-axis

Result: - 1).Cd from graph, Qthe Vs Qact = _______

2). Cd from graph, log (Qact) Vs log(H)= _______

3). Arithmetic mean value of the Cd = _________

Table for observations: -

Table: 1Sl.

No.

Difference in manometer

Limb levels, ’h’ in cm

Rise of water level in collecting

tank

Time taken for

rise Lr, ’T’ in sec

h 1 h 2 h = h 1- h 2 From To Rise Lr , in mm

Table for calculations : -

Table: 2

Sl.

N

o

Qact=

ALr/(1000T

) in m3/ sec

Mean

Velocity,

V=Qact/a in

m/sec

Head difference,

in m of water , H

= 0.126 x h

log

(H)

QThe = A1A2√

2gH)/ √ (A12–

A22)

in m3/ sec

log

(Qact)

Co efficient

of discharge

Cd = Qact /

QThe

Expected Graphs: -

log (Qact) n=Δy/Δx Qact

Cd = slope

log (k)

log (H) Qthe

09. CALIBRATION OF ORIFICE METER

Objective: - To calibrate Orifice meter and to determine the co-efficient of discharge of the given

Orifice meter.

Apparatus: - Orifice meter fixed in a pipeline, manometer, collecting tank, and stopwatch.

Theory: - Orifice meter is a device, which is used to measuring the rate of flow of fluid through a

pipeline. The basic principle on which a Orifice meter works is that by reducing the cross

sectional area of the flow passage, a pressure difference is created between the inlet and

vena-contracta and the measurement of pressure difference enables the determination of

the discharge through the pipe.

An Orifice meter consists of an inlet section followed by a suddenly reduced cross

section in form of orifice. At the inlet section and at the vena-contracta of the Orifice

meter pressure taps are provided through the pressure rings.

Formulae for Calculations: -

1. Basic data contents

(i). Area of the collecting tank, 0.12 m2

(ii). Diameter of the inlet pipeline, d1 = 25mm,

(iii). Diameter of the orifice, d2 = 12.5mm,

2. Theoretical discharge through the pipe line

QThel = A1A2√ 2gH) / √ (A12– A2

2)

Where, H Difference in manometer limb levels, in meters of water;

A1 Cross sectional area of the inlet section of the Orifice, in m2;

A2 Cross sectional area of the Orifice, in m2;

g Acceleration due to gravity in m/sec2

3. Actual discharge through Orifice meter

Qact= A Lr / T

Where, A Area of the collecting tank in meters;

Lr Height of water collected in the collecting tank., in meters

T Time taken in seconds for water collection in sec

4. Co efficient of discharge, Cd

Cd = Qact / QThe

5. To determine k and n (from calibration curve)

Qact = k (H) n where k is a const and k = Cd A1 A2√ 2g) / √ (A12– A2

2)

log (Qact)= n log (H) + log (k) ( i.e y = mx +c form)

Procedure: -1. Switch on the pump and open the delivery valve

7. Open the corresponding ball valve of the Orifice meter pipe

8. Note down the differential head reading in the manometer (expel if any air is trapped by

opening the drain cocks provided with the manometer.)

9. From the known pressure head difference, the ideal discharge is calculated using the

basic formula. The actual discharge is determined by finding time taken for specific

volume of water collection in the collecting tank.

10. Repeat the steps 2 to 4 for different flow rates and note down the readings.

11. After the experiment is over keep supply valve closed, and switch-OFF the pump.

Sample Calculation: -

Precautions: -1.Do not start the pump if the supply voltage is less than 300V,

2. The water in the tank should be clean.

3. See that there should be no water leakage from the Venturi meter connections

Graphs: -To find, co efficient of discharge through graph plot the following graphs

1) Theoretical discharge, Qthe on X-axis Vs Actual discharge, Qact on Y-axis

2) log (Qact) on Y-axis Vs log (H)on X-axis

Result: - 1).Cd from graph, Qthe Vs Qact = _______

2). Cd from graph, log (Qact) Vs log(H)= _______

3). Arithmetic mean value of the Cd = _________

Table for observations: -

Table: 1Sl.

No.

Difference in manometer. Limb levels,

’h’ in cm

Rise of water level in collecting tank Time taken for

rise Lr, ’T’ in

sech 1 h 2 h = h 1- h 2 From To Rise Lr , in mm

Table for calculations : -

Table: 2

Sl.

N

o

Qact=

ALr/(1000T

) in m3/ sec

Mean

Velocity,

V=Qact/a in

m/sec

Head difference,

in m of water ,

H = 0.126 x h

log

(H)

QThe = A1A2√

2gH)/ √ (A12–

A22)

in m3/ sec

log

(Qact)

Co efficient

of discharge

Cd = Qact /

QThe

Expected Graphs: -

log (Qact) n=Δy/Δx Qact

Cd = slope

log (k)

log (H) Qthe

10. FRICTION FACTOR OF A PIPE LINE

Objective: - To determine the co efficient of friction for a given pipeline.

Apparatus: -One given length of pipeline, Manometer, collecting tank and stopwatch etc.

Theory: - When a fluid flows through a pipe, certain resistance is offered to the flowing fluid,

which result in causing of loss of energy. The various energy losses in pipe may be classified

as a). Major losses b). Minor losses. The major loss of energy as a fluid flows through a pipe,

is caused by friction of the pipe walls. The loss of energy due to friction is classified as a

major loss because in case of long pipelines it is usually much more than the loss of energy

incurred by other causes.

Formulae for Calculations: -

1. Basic data contents

(i). Dimensions of the collecting tank, length = 600mm and width = 600mm

(ii). Diameter of the pipeline, d1 = 25mm,

(iii). Length of the pipeline, L = 3450mm,

2. Basic equation

Head loss due to flow over a length L, hf = fLV2 / (2gD)

Where,

D Diameter of pipe in cm, V Mean Velocity in cm/s

f Friction factor of pipe and k f L / (2gD)

Procedure:

1. Switch on the pump and open the delivery valve

2. Open the corresponding ball valve of the pipe

3. Note down the differential head reading in the manometer (expel if any air is trapped

by opening the drain cocks provided with the manometer).

4. The actual discharge is determined by finding time taken for specific volume of water

collection in the collecting tank.

5. Repeat the steps 2 to 4 for different flow rates and note down the readings.

6. After the experiment is over keep supply valve closed, and switch-OFF the pump.

Sample Calculation: -

Precautions: -1). Do not start the pump if the supply voltage is less than rating voltage.

2). The water in the tank should be clean.

Graphs: - a). A graph between V2 on X-axis and hf on Y-axis is drawn.

b). A graph between log10V on X-axis and log10hf on Y-axis is plotted.

Result: - 1). Friction factor from V2 Vs hf curve = _____________________

2). Friction factor from log10V Vs log10 hf curve = ______________

3). Arithmetic mean value of the friction factor = ______________

Table for observations: -

Table: 1Sl.

No.

Difference in manometer

Limb levels, ’h’ in cm

Rise of water level in collecting

tank

Time taken for

rise Lr, ’T’ in sec

h 1 h 2 h = h 1- h 2 From To Rise Lr , in mm

Table for calculations : -

Table: 2

Sl.

No

Actual discharge,

Qact= ALr/(1000T) in

m3/sec

Mean Velocity,

V=Qact/a in

m/sec

Head difference,

in m of water hf =

0.136 x h

C = (2gD) /

L

Friction

factor,

f = C hf / V2

Expected Graphs: -

log10 hf n=Δy/Δx hf

log10 (k)

log10 V V2

11. BERNOULLI’S EXPERIMENT

Objective: - To verify the validity of the Bernoulli’s equation for an incompressible flow.

Apparatus: - Duct of variable cross section with supply and discharge chambers, collecting tank

and stop watch etc.

Theory: - P/w + V2/ (2g) + Z= const. is called Bernoulli’s equation. Each term in this equation

represents the energy possessed by the fluid. Each term in the equation represents the energy

per unit weight of the flowing fluid. The term ‘P/w’ is known as pressure head or static head;

‘V2/ (2g)’ is known as velocity head or kinetic head and ‘Z’ is known as potential head or

datum head. The sum of P/w, V2/ (2g) & Z is known as ‘Total head’ or the total energy per

unit weight of the fluid. The Bernoulli’s equation thus states that in a steady, irrotational flow

of an incompressible fluid the total energy at any point is constant. In other words, if the

Bernoulli’s equation is applied between any two points in a steady irrotational flow of an

incompressible fluid then, we get

P1/w + V12/ (2g) + Z1 = P2/w + V2

2/ (2g) + Z2

Where the different terms with subscripts 1 and 2 correspond to the two points considered.

Formulae for Calculations: -

1) Basic data

Cross sectional area of the pipe at different duct points, in mm2

a1= 491 a2= 377, a3= 245, a4= 153, a5= 123

a6= 153, a7= 202, a8= 279, a9= 369, a10= 491

2) Basic equation

Total Head, H = P/w + V2/ (2g) + Z

Where, P/w Pressure head, V2/ (2g) Pressure head

Z Elevation head above any arbitrary datum.

Procedure: - 1). The inflow valve is opened so that water flows into the supply chamber and heads

up.

2). Flow through the duct is controlled by the outlet valve located at down stream.

3). At steady flow, all the readings should be noted down simultaneously.

4). The discharge is measured in the collecting tank.

5). Repeat the steps no. 3 and 4 for different flow patterns

6). After the experiment is over keep supply valve closed, and switch-OFF the pump.

Precautions: -1.Do not start the pump if the supply voltage is less than the rating voltage.

2. The water in the tank should be clean.

Graphs: -Duct points on X-axis Vs Pressure head, velocity head, elevation head and Total head on

Y-axis and on the same graph.

Result: - Bernoulli’s equation is verified by conducting an experiment.

Table for calculations Table-1

Time taken in Piezo tubes reading at duct points in mm of water

Sl.

No.

Height of water

collected ‘h’ in

mm

seconds for water

collection, ‘T’ in sec

1 2 3 4 5 6 7 8 9 10

1

2

3

Table for calculations Table-2

Sl.

No

Duct

point

Actual discharge

Qact =

Ah/(1000T)

Velocity,

Vi=Qact/ai

Where, i =1 to

10

V2/ (2g) P/w Z H

I

II

1

2

3

4

5

6

7

8

9

10

1

2

3

4

5

6

7

8

9

10

12.PELTON WHEEL TURBINE at Constant speed

Objective: - To study the characteristic curves of a Pelton wheel turbine at constant speed condition.

Apparatus:- stop clock, meter scale, Pelton wheel turbine setup, 3-phase power supply.

Theory: - Pelton wheel is a tangential flow high head impulse turbine. Water from the nozzle strikes

the buckets tangentially to the runner wheel. Total energy of the water at the outlet of the

nozzle is in the form of kinetic energy. The pressure at the inlet and outlet of the Turbine is

atmospheric pressure.

Formulae for Calculations: -

1). Head on Turbine in meters of water, H

H = 10P, Where Pis the pressure guage reading in kg/cm2

2). Flow rate of water through Turbine

Qact = 8/15 x Cd√ 2g tan (θ/2) h5/2

Assuming, Cd = 0.6, g= 9.81m/sec2, θ= 60

h Head over the notch in meters

3). Hydraulic input to the Turbine

H.Ppump = wQH/75

Where, w 1000kg/m3; H Head over the Turbine in meters of water.

4). Brake Horse Power (BHP) of Turbine

B.H.P = [2ΠN(F1-F2)r] / 4500

Where, F1 and F2 Spring balance readings in kgf

r Radius of the brake drum in meters (r = 0.15m)

5). Turbine Efficiency

ηtur = (B.H.P / H.Phyd) x 100

6). Percentage of Full Load

% Full load = (Part load B.H.P / Maximum load B.H.P) x 100

Procedure: -1Keep the butterfly valve and sphere valve closed,

2. Keep the brake drum loading at minimum (zero),

3. Press the green button of the supply pump starter. The pump picks up full speed and

become operational,

4. Now keep the butterfly valve opening at minimum,

6. Slowly open the sphere valve so that the Turbine runner picks up the speed and attains the

maximum at full opening of the valve,

7. At one particular head on the Turbine note down the speed, head over notch, brake loads

and tabulate the readings

8. Repeat the step no. 7 at different brake loads and note down the readings of speed

9. After the experiment is over keep sphere valve and butterfly valve closed, and switch-

OFF the pump.

Sample Calculation: -

Precautions: -1. The water in the sump tank should be clean.

2. To start and stop supply pump, keep gate valve closed.

3. It is recommended to close sphere valve before starting.

Graphs: -To study constant head characteristic curves of a Pelton wheel Turbine plot the following

graphs,

i). Discharge, Q on X- axis Vs ηturbine on Y- axis

ii). Discharge, Q on X- axis Vs B.H.P on Y- axis

iii) % of Full load on X- axis Vs ηoverall on Y- axis

Result: - 1. The constant speed characteristic curves of Pelton wheel have been obtained

2. The maximum efficiency of the pelton wheel turbine is=______

Table for Observations: -

Table: 1Sl.

No.

Runner speed,

‘N’ in RPM

Head over the

Turbine, ‘P’ in

kgf/cm2

Head over the

notch, ‘h’ in

meters

Spring balance reading in

kgf

F1 F2

Tables for Calculations: -

Table: 2

Sl.

No.

Net Head, H

in meters

Flow rate, Q in

m3/secH.Phyd B.H.P ηturbine

% Of

Full load

Expected Graphs: -

% Full load Vs Q

ηturbine Vs Q

BHP Vs Q

Q

13. KAPLAN TURBINE at Constant speed condition

Objective: - To study the characteristic curves of a Kaplan turbine at constant speed condition.

Apparatus: - stop clock, meter scale, Francis turbine setup, 3-phase power supply.

Theory: - Kaplan turbine is a reaction turbine operated at low head. It consists of guide vanes,

runner, scroll casing and draft tube at the exit. Water turns through right angles and guided

through 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 operation. By varying the guide vane angles, high efficiency can be maintained

over a wide range of operating conditions. After passing through the turbine, water enters

into the collecting tank through draft tube. Loading of the turbine can be done by electrical

switches arrangement. (Electrical loading)

Formulae for Calculations: -

1). Head on Turbine in meters of water, H

H = 10(P + Pv / 760)

Where P pressure gauge reading in kg/cm2

Pv Vacuum pressure gauge reading in mm of Hg

2). Flow rate of water through Turbine

Q = 2.95 x L x h3/2

Where, L Crest width in meters (L= 0.5m)

h Head over the notch in meters

3). Hydraulic input to the Turbine

H.Phyd = wQH/75

Where, w 1000kg/m3;

Q Flow rate of water, in m3/s

H Head over the Turbine in meters of water.

4). Electric power as indicated by the energy meter

H.Pelec = (5/1500) x (1000/736) x (60x60)/t = 16.3 / t

Where, t it is the time taken for 5 revolutions of the energy meter in sec.

5). Brake Horse Power (BHP) of Turbine

B.H.P = H.Pelec / ηgenerator

Where, ηgenerator Generator Efficiency (ηgenerator =75%)

6). Turbine Efficiency

ηturbine = (B.H.P / H.Phyd) x 100

7). Percentage of full load

% Full load = (Part load B.H.P / Maximum load B.H.P) x 100

Procedure: - 1. Keep the brake drum loading at minimum (zero),

2. Press the green button of the supply pump starter. The pump picks up full speed and

become operational,

3. Slowly open the gate valve so that the Turbine runner picks up the speed and get the

required speed at any particular guide vane angle.

4. At one particular head on the Turbine note down the speed, head over notch, wattage of

electrical load bulbs in action, load on generator, energy meter reading and tabulate the

readings

5. Repeat the step no. 4 at different electrical bulb loads by keeping the rotor pitch constant

and changing the gate position and note down the readings.

6. After the experiment is over keep gate valve closed, and switch-OFF the pump.

Sample Calculation: -

Fig: Sectional arrangement of Kaplan Turbine

Precautions: -1. The water in the sump tank should be clean.

2. To start and stop supply pump, keep gate valve closed.

3. It is recommended to close guide vanes before starting.

Graphs: -To study constant speed characteristic curves of a Kaplan Turbine plot the following

graphs,

i). Discharge, Q on X- axis Vs ηturbine on Y- axis

ii). Discharge, Q on X- axis Vs B.H.P on Y- axis

iii) % of Full load on X- axis Vs ηoverall on Y- axis

Result: - 1. The constant speed characteristic curves of Kaplan turbine have been obtained

2. The maximum efficiency of the Kaplan turbine is=______

Sl.

No.

Runner

speed, ‘N’

in RPM

Head over the TurbineHead

over the

notch, ‘h’

in meters

Load on

generatorWattage

of bulbs

in action

Time taken for 5

rev. of Energy

meter reading, ‘t’

sec.

‘P’ in

kgf/cm2

Pv in mm of

Hg

V in

Volts

I in

Amps

Table for Observations: -

Tables for Calculations: -

Table: 2

Sl.

No.

Net Head, H

in meters

Flow rate, Q

in m3/secH.Phyd B.H.P ηturbine

% of Full

load

Expected Graphs: -

% Full load Vs Q

ηturbine Vs Q

BHP Vs Q

Q

14. FRANCIS TURBINE at Constant speed condition

Objective: - To study the characteristic curves of a Francis turbine at constant speed condition.

Apparatus: - stop clock, meter scale, Francis turbine setup, 3-phase power supply.

Theory: - Francis turbine is a reaction turbine operated at medium head. It consists of guide vanes,

runner, scroll casing and draft tube at the exit. Water turns through right angles and guided

through the runner and thus rotating the runner shaft. By varying the guide vane angles, high

efficiency can be maintained over a wide range of operating conditions. After passing

through the turbine, water enters into the collecting tank through draft tube. Loading of the

turbine can be done by brake drum arrangement.

Formulae for Calculations: -

1). Head on Turbine in meters of water, H

H = 10(P + Pv / 760)

Where P pressure gauge reading in kg/cm2

Pv Vacuum pressure gauge reading in mm of Hg

2). Flow rate of water through Turbine

Q = 2/3 x b x Cd√ 2g h3/2

Assuming, Cd = 0.6, g= 9.81m/sec2, b = 0.5m

h Head over the notch in meters

3). Hydraulic input to the Turbine

H.Phyd = wQH/75

Where, w 1000kg/m3;

Q Flow rate of water, in m3/s

H Head over the Turbine in meters of water.

4). Brake Horse Power (BHP) of Turbine

B.H.P = [2ΠN(F1-F2)r] / 4500

Where, F1 and F2 Spring balance readings in kgf

r Radius of the brake drum in meters (r = 0.15m)

5). Turbine Efficiency

ηtur = (B.H.P / H.Phyd) x 100

6). Percentage of full load

% Full load = (Part load B.H.P / Maximum load B.H.P) x 100

Procedure: - 1. Keep the butterfly valve and gate valve closed,

2. Keep the brake drum loading at minimum (zero),

3. Press the green button of the supply pump starter. The pump picks up full speed and

become operational,

4. Slowly open the gate valve so that the Turbine runner picks up the speed and get the

required speed at any particular guide vane angle.

5. At one particular speed of the Turbine note down the head over the turbine, head over

notch, brake loads and tabulate the readings

6. Repeat the step no. 5 at different brake loads by keeping gate valve position as constant and

changing the guide vanes position.

7. After the experiment is over keep sphere valve and butterfly valve closed, and switch-

OFF the pump.

Sample Calculation: -

Fig: Sectional arrangement of Francis Turbine

Precautions: -1. The water in the sump tank should be clean.

2. To start and stop supply pump, keep gate valve closed.

3. It is recommended to close guide vanes before starting.

Graphs: -To study constant speed characteristic curves of a Francis Turbine plot the following

graphs,

i). Discharge, Q on X- axis Vs ηturbine on Y- axis

ii). Discharge, Q on X- axis Vs B.H.P on Y- axis

iii) % of Full load on X- axis Vs ηoverall on Y- axis

Result: - 1. The constant speed characteristic curves of Francis Turbine have been obtained

2. The maximum efficiency of the Francis turbine is=______

Table for Observations: -

Table: 1

Sl.

No.

Runner

speed, ‘N’

in RPM

Head over the Turbine Head over the

notch, ‘h’ in

meters

Spring balance reading in

kgf

‘P’ in

kgf/cm2

Pv in mm of

HgF1 F2

Tables for Calculations: -

Table: 2

Sl.

No.

Net Head, H

in meters

Flow rate, Q

in m3/secH.Phyd B.H.P ηturbine

% of

Full load

Expected Graphs: -

% Full load Vs Q

ηturbine Vs Q

BHP Vs Q

Q

15. RECIPROCATING PUMP TEST RIG. Multispeed condition

Objective: - To conduct performance test on a Reciprocating pump at variable speed condition

Apparatus: -Reciprocating pump test set-up, stop clock, meter scale etc.

Theory:-In general a pump may be defined as a mechanical device which when interposed in a

pipe-line converts mechanical energy supplied to it from some internal source in to hydraulic

energy thus resulting in the flow of liquid from the lower potential/head to the higher

potential/head.

Reciprocating pump is a positive displacement pump, which is having a plunger

(piston) moves to and fro in a closed cylinder. The cylinder is connected to suction and

delivery pipes and are lifted with non-return valves to admit the liquid in one direction only.

The non-return valve at the suction side, allows the liquid only to enter the cylinder and the

delivery non-return valve allows the liquid only to escape out from the cylinder to the delivery

pipe.

For more uniform flow, an air vessel is fitted before the suction valve, and after

delivery valve. This contributes for more uniform flow of liquid also saves energy input to the

pump from the prime mover.

Formulae for Calculations: -

1). Basic data contents

(i). 1kg/cm2 = 760 mm of Hg (10m of water)

(ii). Density of water, ‘w’ = 1000 kg/m3

(iii). Energy meter constant = 1500rev/1kWh

(iv). Area of collecting tank, ‘A’ = 0.125m2

2). Electric power as indicated by the energy meter

H.Pelec = (5/1500) x (1000/736) x (60x60)/t = 16.3 / t

Where, t it is the time taken for 5 revolutions of the energy meter in sec.

3). Shaft Horse Power as indicated by swinging field dynamometer

H. Pshaft = 2Π NT / 4500 = 2Π N x 0.1 x F /4500 = 0.00014 N F

Where, F Spring balance readings in kgf

r Radius of the swing field arm in meters (r = 0.1m)

N The RPM of the DC motor

4). Discharge rate ‘Q’ in m3/sec

Q=(A x h) / (1000 x T) = 0.125h/1000T

where, A 0.125m2 , is the area of collecting tank,

h Height of water collected in the collecting tank., in mm

T Time taken in seconds for water collection in sec.

5). Total head ‘H’ in meters

H = 10 x (Delivery pressure + Vacuum head)

H = 10(P + Pv/760)

Where, P Pressure (at stage 4)in kg/cm3, Pv Vacuum pressure in mm of Hg.

6). Hydraulic H.P (Delivered by the pump)

H.Ppump = wQH/75

Where, w 1000kg/m3; H Total/ Manometric head in meters.

7). Pump Efficiency

ηpump = H.Ppump / H.Pshaft x 100

8). Overall Efficiency

ηoverall = H.Ppump/ H.Pelec x 100

Procedure: - 1). Fill the sump tank with clean water,

2. Keep the delivery and suction valves open,

3. Switch on the mains, so that the mains-ON indicator glows. Now switch-ON the

controller,

4. Ste the desired speed using stepped pulley and belt arrangement

5. Note down the pressure gauge, vacuum gauge and time for number of revolutions of

energy meter disc at a particular load condition (i.e Close the delivery valve partially

until we get a particular delivery pressure)

6. Operate the butterfly valve to note down the collecting tank reading against the known

time, keep it open when the readings are not taken.

7. Repeat the steps 5 & 6 for different speeds of the pump by keeping load as constant.

8. After the experiment is over keep all the delivery and suction valves open and switch-

OFF the pump.

Sample Calculation: -

Precautions: -1.Do not start the pump if the supply voltage is less than 180V,

2. The water in the sump tank should be clean.

3. Initially the suction and delivery valves should be kept fully open,

Graphs: -To study the operating characteristic curves of a Reciprocating pump, plot the following

graphs,

i). Rotational speed of the pump, ‘N’ on X-axis Vs Discharge, ‘Q’ on Y-axis

ii). Rotational speed of the pump, ‘N’ on X-axis Vs Shaft Input power, on Y-axis

iii). Rotational speed of the pump, ‘N’ on X-axis Vs ηpump on Y-axis

Result: - 1. The performance test on a Reciprocating pump has been conducted

2. The maximum efficiency of the Reciprocating pump is =

Table for Observations: -

Table: 1

Sl.

No.

Pump

Speed,

‘N’ in

RPM

Delivery

head

pressure, P in

kg/cm2

Suction head

(Vacuum), Pv

in mm of Hg

Time taken for 5

rev. of Energy

meter reading, ‘t’

in sec.

Height of

water

collected,

‘h’ in mm

Discharge

time. ‘T’ in

sec

Table for Calculations: -

Table: 2

Sl. No.Total Head,

H in meters

Rate of discharge,

‘Q’ in m3/secH.Ppump H.Pshaft

H.Pel

ec

ηpum

p

ηoverall

Expected Graphs: -

Q Vs N

P Vs N

ηpumpVs N

N

CALIBRATION OF VENTURI METER

Aim: - To calibrate venturimeter and to determine the co-efficient of discharge of the given

venturimeter.

Apparatus: -Venturi meter fixed in a pipeline, manometer, collecting tank, stop watch.

Theory: -Venturi meter is a device which is used to measuring the rate of flow of fluid through a

pipeline. The basic principle on which a Venturi meter works is that by reducing the cross

sectional area of the flow passage, a pressure difference is created between the inlet and

throat and the measurement of pressure difference enables the determination of the

discharge through the pipe.

A Venturi meter consists of i). An inlet section followed by a convergent cone

section, ii). A cylindrical throat and iii). A gradually divergent cone section. At the inlet

section and at the throat of the Venturi meter pressure taps are provided through the

pressure rings.

Formulae for Calculations: -

4. Basic data contents

(i). Dimensions of the collecting tank, length = 600mm and width = 600mm

(ii). Diameter of the pipeline, d1 = 50mm,

(iii). Diameter of the throat, d2 = 25mm,

5. Theoretical discharge through the pipe line

QThel = A1A2√ 2gH) / √ (A12– A2

2)

Where, H Difference in manometer limb levels, in meters of water;

A1 Cross sectional area of the inlet section of the Venturi, in m2;

2 Cross sectional area of the Outlet section of the Venturi, in m2;

g Acceleration due to gravity in m/sec2

6. Actual discharge through Venturi meter

Qact= A Lr / T

Where, A Area of the collecting tank in meters;

Lr Height of water collected in the collecting tank., in meters

T Time taken in seconds for water collection in sec

3. Co efficient of discharge, Cd

Cd = Qact / QThe

6. To determine k and n (from calibration curve)

Qact = k (H) n where k is a const and k = Cd A1 A2√ 2g) / √ (A12– A2

2)

log (Qact)= n log (H) + log (k) ( i.e y = mx +c form)

Procedure: -1. Switch on the pump and open the delivery valve

12. Open the corresponding ball valve of the venturimeter pipes

13. Note down the differential head reading in the manometer (expel if any air is trapped by

opening the drain cocks provided with the manometer.)

14. From the known pressure head difference, the ideal discharge is calculated using the

basic formula. The actual discharge is determined by finding time taken for specific

volume of water collection in the collecting tank.

15. Repeat the steps 2 to 4 for different flow rates and note down the readings.

16. After the experiment is over keep supply valve closed, and switch-OFF the pump.

Sample Calculation: -

Precautions: -1.Do not start the pump if the supply voltage is less than 300V,

2. The water in the tank should be clean.

3. See that there should be no water leakage from the Venturi meter connections

Graphs: -To find, co efficient of discharge through graph plot the following graphs

3. Theoretical discharge, Qthe on X-axis Vs Actual discharge, Qact on Y-axis

4. log (Qact) on Y-axis Vs log (H)on X-axis

Result: - 1).Cd from graph, Qthe Vs Qact = _______

2). Cd from graph, log (Qact) Vs log(H)= _______

3). Arithmetic mean value of the Cd = _________

Table for observations: -

Table: 1Sl.

No.

Difference in manometer

Limb levels, ’h’ in cm

Rise of water level in collecting

tank

Time taken for

rise Lr, ’T’ in sec

h 1 h 2 h = h 1- h 2 From To Rise Lr , in mm

Table for calculations : -

Table: 2

Sl.

N

o

Qact=

ALr/(1000T

) in m3/ sec

Mean

Velocity,

V=Qact/a in

m/sec

Head

difference,

in m of

water

H = 0.136 x

h

log

(H)

QThe = A1A2√

2gH)/ √ (A12–

A22)

in m3/ sec

log

(Qact)

Co efficient

of discharge

Cd = Qact /

QThe

Expected Graphs: -

log (Qact) n=Δy/Δx Qact

Cd = slope

log (k)

log (H) Qthe

CALIBRATION OF ORIFICE METER

Aim: - To calibrate Orifice meter and to determine the co-efficient of discharge of the given Orifice

meter.

Apparatus: - Orifice meter fixed in a pipeline, manometer, collecting tank, stop watch.

Theory: - Orifice meter is a device which is used to measuring the rate of flow of fluid through a

pipeline. The basic principle on which a Orifice meter works is that by reducing the cross

sectional area of the flow passage, a pressure difference is created between the inlet and

vena-contracta and the measurement of pressure difference enables the determination of

the discharge through the pipe.

An Orifice meter consists of an inlet section followed by a suddenly reduced cross

section in form of orifice. At the inlet section and at the vena-contracta of the Orifice

meter pressure taps are provided through the pressure rings.

Formulae for Calculations: -

7. Basic data contents

(i). Dimensions of the collecting tank, length = 600mm and width = 600mm

(ii). Diameter of the inlet pipeline, d1 = 50mm,

(iii). Diameter of the orifice, d2 = 25mm,

8. Theoretical discharge through the pipe line

QThel = A1A2√ 2gH) / √ (A12– A2

2)

Where, H Difference in manometer limb levels, in meters of water;

A1 Cross sectional area of the inlet section of the Orifice, in m2;

A2 Cross sectional area of the Orifice, in m2;

g Acceleration due to gravity in m/sec2

9. Actual discharge through Orifice meter

Qact= A Lr / T

Where, A Area of the collecting tank in meters;

Lr Height of water collected in the collecting tank., in meters

T Time taken in seconds for water collection in sec

3. Co efficient of discharge, Cd

Cd = Qact / QThe

7. To determine k and n (from calibration curve)

Qact = k (H) n where k is a const and k = Cd A1 A2√ 2g) / √ (A12– A2

2)

log (Qact)= n log (H) + log (k) ( i.e y = mx +c form)

Procedure: -1. Switch on the pump and open the delivery valve

17. Open the corresponding ball valve of the Orifice meter pipe

18. Note down the differential head reading in the manometer (expel if any air is trapped by

opening the drain cocks provided with the manometer.)

19. From the known pressure head difference, the ideal discharge is calculated using the

basic formula. The actual discharge is determined by finding time taken for specific

volume of water collection in the collecting tank.

20. Repeat the steps 2 to 4 for different flow rates and note down the readings.

21. After the experiment is over keep supply valve closed, and switch-OFF the pump.

Sample Calculation: -

Precautions: -1.Do not start the pump if the supply voltage is less than 300V,

2. The water in the tank should be clean.

3. See that there should be no water leakage from the Venturi meter connections

Graphs: -To find, co efficient of discharge through graph plot the following graphs

5. Theoretical discharge, Qthe on X-axis Vs Actual discharge, Qact on Y-axis

6. log (Qact) on Y-axis Vs log (H)on X-axis

Result: - 1).Cd from graph, Qthe Vs Qact = _______

2). Cd from graph, log (Qact) Vs log(H)= _______

3). Arithmetic mean value of the Cd = _________

Table for observations: -

Table: 1Sl.

No.

Difference in manometer

Limb levels, ’h’ in cm

Rise of water level in collecting

tank

Time taken for

rise Lr, ’T’ in sec

h 1 h 2 h = h 1- h 2 From To Rise Lr , in mm

Table for calculations : -

Table: 2

Sl.

N

o

Qact=

ALr/(1000T

) in m3/ sec

Mean

Velocity,

V=Qact/a in

m/sec

Head

difference,

in m of

water

H = 0.136 x

h

log

(H)

QThe = A1A2√

2gH)/ √ (A12–

A22)

in m3/ sec

log

(Qact)

Co efficient

of discharge

Cd = Qact /

QThe

Expected Graphs: -

log (Qact) n=Δy/Δx Qact

Cd = slope

log (k)

log (H) Qthe

BERNOULLI’S EXPERIMENT

Objective: - To verify the validity of the Bernoulli’s equation for an incompressible flow.

Apparatus: - Duct of variable cross section with supply and discharge chambers, collecting tank

and stop watch etc.

Theory: - P/w + V2/ (2g) + Z= const. is called Bernoulli’s equation. Each term in this equation

represents the energy possessed by the fluid. Each term in the equation represents the energy

per unit weight of the flowing fluid. The term ‘P/w’ is known as pressure head or static head;

‘V2/ (2g)’ is known as velocity head or kinetic head and ‘Z’ is known as potential head or

datum head. The sum of P/w, V2/ (2g) & Z is known as ‘Total head’ or the total energy per

unit weight of the fluid. The Bernoulli’s equation thus states that in a steady, irrotational flow

of an incompressible fluid the total energy at any point is constant. In other words, if the

Bernoulli’s equation is applied between any two points in a steady irrotational flow of an

incompressible fluid then, we get

P1/w + V12/ (2g) + Z1 = P2/w + V2

2/ (2g) + Z2

Where the different terms with subscripts 1 and 2 correspond to the two points considered.

Formulae for Calculations: -

3) Basic data

Cross sectional area of the pipe at different duct points, in mm2

a1= 490.87, a2= 376.68, a3= 260.16, a4= 162.86, a5= 128.68,

a6= 153.94, a7= 213.82, a8= 292.55, a9= 376.69, a10= 490.87.

4) Basic equation

Total Head, H = P/w + V2/ (2g) + Z

Where, P/w Pressure head, V2/ (2g) Pressure head

Z Elevation head above any arbitrary datum.

Procedure: - 1). The inflow valve is opened so that water flows into the supply chamber and heads

up.

2). Flow through the duct is controlled by the outlet valve located at down stream.

3). At steady flow, all the readings should be noted down simultaneously.

4). The discharge is measured in the collecting tank.

5). Repeat the steps no. 3 and 4 for different flow patterns

6). After the experiment is over keep supply valve closed, and switch-OFF the pump.

Precautions: -1.Do not start the pump if the supply voltage is less than the rating voltage.

2. The water in the tank should be clean.

Graphs: -Duct points on X-axis Vs Pressure head, velocity head, elevation head and Total head on

Y-axis and on the same graph.

Result: -

Table for calculations Table-1

Sl.

No.

Height of water

collected ‘h’ in

mm

Time taken in

seconds for water

collection, ‘T’ in sec

Piezo tubes reading at duct points in mm of water

1 2 3 4 5 6 7 8 9 10

1

2

3

Table for calculations Table-2

Sl.

No

Duct

point

Actual discharge

Qact =

Ah/(1000T)

Velocity,

Vi=Qact/ai

Where, i =1 to

10

V2/ (2g) P/w Z H

I

II

III

1

2

3

4

5

6

7

8

9

10

1

2

3

4

5

6

7

8

9

10

1

2

3

4

5

6

7

8

9

10

PELTON WHEEL TURBINE

Objective: - To study the characteristic curves of a Pelton wheel turbine at constant head condition.

Apparatus:- stop clock, meter scale, Pelton wheel turbine setup, 3-phase power supply.

Theory: - Pelton wheel is a tangential flow high head impulse turbine. Water from the nozzle strikes

the buckets tangentially to the runner wheel. Total energy of the water at the outlet of the

nozzle is in the form of kinetic energy. The pressure at the inlet and outlet of the Turbine is

atmospheric pressure.

Formulae for Calculations: -

1). Head on Turbine in meters of water, H

H = 10P

Where Pis the pressure guage reading in kg/cm2

2). Flow rate of water through Turbine

Qact = 8/15 x Cd√ 2g tan (θ/2) h5/2

Assuming, Cd = 0.6, g= 9.81m/sec2, θ= 60

h Head over the notch in meters

3). Hydraulic input to the Turbine

H.Ppump = wQH/75

Where, w 1000kg/m3;

H Head over the Turbine in meters of water.

4). Brake Horse Power (BHP) of Turbine

B.H.P = [2ΠN(F1-F2)r] / 4500

Where, F1 and F2 Spring balance readings in kgf

r Radius of the brake drum in meters (r = 0.15m)

5). Turbine Efficiency

ηtur = (B.H.P / H.Phyd) x 100

6). Unit quantities under unit head

(a). Unit Speed; Nu = N / √ H

(b). Unit Power; Pu = P / H3/2

( c). Unit discharge; Qu = Q / √ H

7). Specific Speed

Ns = N √ P / H5/4

Procedure:-1. Fill up the sump tank with clean water,

2. Keep the butterfly valve and sphere valve closed,

3. Keep the brake drum loading at minimum (zero),

4. Press the green button of the supply pump starter. The pump picks up full speed and

become operational,

5. Now keep the butterfly valve opening at minimum,

6. Slowly open the sphere valve so that the Turbine runner picks up the speed and attains the

maximum at full opening of the valve,

7. At one particular head on the Turbine note down the speed, head over notch, brake loads

and tabulate the readings

8. Repeat the step no. 8 at different brake loads and note down the readings of speed

9. After the experiment is over keep sphere valve and butterfly valve closed, and switch-

OFF the pump.

Sample Calculation: -

Precautions: -1.Do not start the pump if the supply voltage is less than 300V,

2. The water in the sump tank should be clean.

3. To start and stop supply pump, keep gate valve closed.

4. It is recommended to close sphere valve before starting.

Graphs: -To study constant head characteristic curves of a Pelton wheel Turbine plot the following

graphs,

i). Unit Speed, Nu Vs Unit Power, Pu,

ii). Unit Speed, Nu Vs Unit discharge, Qu

iii). Unit Speed, Nu Vs ηoverall

Result: -

Table for Observations: -

Table: 1Sl.

No.

Runner speed,

‘N’ in RPM

Head over the

Turbine, ‘P’ in

kgf/cm2

Head over the

notch, ‘h’ in

meters

Spring balance reading in

kgf

F1 F2

Tables for Calculations: -

Table: 2

Sl.

No.

Speed, N in

RPM

Net Head, H in

meters

Flow rate , Q in

m3/sec

H.Phyd B.

H.

P

ηturbi

ne

Table: 3

Sl.

No.

Net Head, H in

m

Unit Speed,

Nu

Unit Power,

Pu

Unit Discharge,

Qu

Specific

speed, Ns

ηturbi

ne

Expected Graphs: -

Qu Vs Nu

Pu Vs Nu

ηpumpVs Nu

Nu

RECIPROCATING PUMP TEST RIG.

Objective: - To obtain the operational characteristic curves of a Reciprocating pump.

Apparatus:-Reciprocating pump test set-up, stop clock, meter scale etc.

Theory:-In general a pump may be defined as a mechanical device which when interposed in a

pipe-line converts mechanical energy supplied to it from some internal source in to hydraulic

energy thus resulting in the flow of liquid from the lower potential/head to the higher

potential/head.

Reciprocating pump is a positive displacement pump, which is having a plunger

(piston) moves to and fro in a closed cylinder. The cylinder is connected to suction and

delivery pipes and are lifted with non-return valves to admit the liquid in one direction only.

The non-return valve at the suction side, allows the liquid only to enter the cylinder and the

delivery non-return valve allows the liquid only to escape out from the cylinder to the delivery

pipe.

For more uniform flow, an air vessel is fitted before the suction valve, and after

delivery valve. This contributes for more uniform flow of liquid also saves energy input to the

pump from the prime mover.

Formulae for Calculations: -

1). Basic data contents

(i). 1kg/cm2 = 760 mm of Hg (10m of water)

(ii). Density of water, ‘w’ = 1000 kg/m3

(iii). Energy meter constant = 1500rev/1kWh

(iv). Area of collecting tank, ‘A’ = 0.125m2

2). Electric power as indicated by the energy meter

H.Pelec = (5/1500) x (1000/736) x (60x60)/t = 16.3 / t

Where, t it is the time taken for 5 revolutions of the energy meter in sec.

3). Shaft Horse Power as indicated by swinging field dynamometer

H. Pshaft = 2Π NT / 4500 = 2Π N x 0.1 x F /4500 = 0.00014 N F

Where, F Spring balance readings in kgf

r Radius of the swing field arm in meters (r = 0.1m)

N The RPM of the DC motor

4). Discharge rate ‘Q’ in m3/sec

Q=(A x h) / (1000 x T) = 0.125h/1000T

where, A 0.125m2 , is the area of collecting tank,

h Height of water collected in the collecting tank., in mm

T Time taken in seconds for water collection in sec.

5). Total head ‘H’ in meters

H = 10 x (Delivery pressure + Vacuum head)

H = 10(P + Pv/760)

Where, P Pressure (at stage 4)in kg/cm3,

Pv Vacuum pressure in mm of Hg.

6). Hydraulic H.P (Delivered by the pump)

H.Ppump = wQH/75

Where, w 1000kg/m3;

H Total/ Manometric head in meters.

7). Pump Efficiency

ηpump = H.Ppump / H.Pshaft x 100

8). Overall Efficiency

ηoverall = H.Ppump/ H.Pelec x 100

Procedure: - 1). Fill the sump tank with clean water,

2. Keep the delivery and suction valves open,

3. Keep the speed control knob at zero,

3. Switch on the mains, so that the mains-ON indicator glows. Now switch-ON the

controller,

4. Ste the desired speed using the controller knob and digital RPM indicator

5. Note down the pressure gauge, vacuum gauge and time for number of revolutions of

energy meter disc at full opening of delivery and suction valves,

6. Operate the butterfly valve to note down the collecting tank reading against the known

time, keep it open when the readings are not taken.

7. Repeat the experiment for different openings of the delivery valve.

8. After the experiment is over keep all the delivery and suction valves open and switch-

OFF the pump.

Sample Calculation: -

Precautions: -1.Do not start the pump if the supply voltage is less than 180V,

2. The water in the sump tank should be clean.

3. Initially the suction and delivery valves should be kept fully open,

4. Accurate readings must be taken to get the good results.

Graphs: -To study the operating characteristic curves of a Reciprocating pump, plot the following

graphs,

i). Total head, ‘H’ on X-axis Vs Discharge, ‘Q’ on Y-axis

ii). Total head, ‘H’ on X-axis Vs Shaft Input power, on Y-axis

iii). Total head, ‘H’ on X-axis Vs ηpump on Y-axis

Result: -

Table for Observations: -

Table: 1Sl.

No.

Pump

Speed,

‘N’ in

RPM

Delivery

head

pressure, P

in kg/cm2

Suction

head

(Vacuum),

Pv in mm of

Hg

Swinging field

spring balance

reading , ‘F’ in

kgf

Time taken for 5

rev. of Energy

meter reading,

‘t’ in sec.

Height of

water

collected,

‘h’ in

mm

Dis

cha

rge

time

. ‘T’

in

sec

Table for Calculations: -

Table: 2Sl.

No.

Pump

Speed, ‘N’

in RPM

Total

Head, H in

meters

Rate of

discharge, ‘Q’

in m3/sec

H.Ppum

p

H.Pshaft H.

Pele

c

ηp

um

p

ηover

all

Expected Graphs: -

Q Vs H

P Vs H

ηpumpVsH

H

MULTISTAGE CENTRIFUGAL PUMP TEST RIG.

Objective: - To plat the operational characteristic curves of a multistage centrifugal pump.

Apparatus:-Multistage (4-stage) centrifugal pump test set-up, stop clock, steel rule etc.

Theory:-In general a pump may be defined as a mechanical device which when interposed in a

pipe-line converts mechanical energy supplied to it from some internal source in to

hydraulic energy thus resulting in the flow of liquid from the lower potential/head to the

higher potential/head.

Multistage centrifugal pump falls in to the category of Roto-dynamic pumps. In these

pumps the liquid is made to rotate in a closed chamber/casing thus creating the centrifugal

action, which gradually builds the pressure gradient towards outlet, thus resulting in the

continuous flow. Hydraulic head developed by the centrifugal pump is low hence; it is not

suitable for high heads as compared to the reciprocating pumps of same capacity and stage.

But if the pump is of multistage construction the pressure gradually builds up in successive

stages all most equally in a stage.

Formulae for Calculations: -

1). Basic data contents

(i). 1kg/cm2 = 760 mm of Hg (10m of water)

(ii). Density of water, ‘w’ = 1000 kg/m3

(iii). Energy meter constant = 150rev/1kWh

(iv). Area of collecting tank, ‘A’ = 0.25m2

2). Discharge rate ‘Q’ in m3/sec

Q=(A x h) / (1000 x T) = 0.25h/1000T

Where, A 0.25m2 , is the area of collecting tank,

h Height of water collected in the collecting tank., in mm

T Time taken in seconds for water collection in sec.

3). Total head ‘H’ in meters

H = 10 x (Delivery pressure + Vacuum head)

H = 10(P + Pv/760)

Where, P Pressure (at stage 4)in kg/cm3,

Pv Vacuum pressure in mm of Hg.

4). Electric power as indicated by the energy meter

H.Pelec = (10/150) x (1000/736) x (60x60)/t = 32.61 x 10/t

Where, t It is the time taken for 10 revolutions of the energy meter in sec.

5). Hydraulic H.P (Delivered by the pump)

H.Ppump = wQH/75

Where, w 1000kg/m3;

H Total/ Manometric head in meters.

6). Pump Efficiency

ηpump = H.Ppump / (H.Pelec x ηmotor) x 100

Where, ηmotor Assumed as 70%;

ηoverall = H.Ppump/H.Pelec x 100

Procedure:-1. Fill the sump tank with clean water,

2. Keep the delivery and suction valves open,

3. Switch on the mains, so that the mains-ON indicator glows. Now switch-ON the pump,

4. Close the delivery valve slightly so that the delivery pressure is readable.

5. Operate the delivery valve to note down the collecting tank reading against the known

time, keep it open when the readings are not taken.

6. Note down the pressure at each stage and also other readings,

7. Repeat the experiment for different openings of delivery valve.

8. After the experiment is over keep all the delivery and suction valves open and switch-

OFF the pump.

Sample Calculation: -

Precautions: -1.Do not start the pump if the supply voltage is less than 300V,

2. The water in the sump tank should be clean.

3. Accurate readings must be taken to get the good results.

Graphs: -To analysis the operating characteristic curves of a multi stage centrifugal pump, plot the

following graphs,

i). Discharge, ‘Q’ Vs Manometric Head, ‘H’

ii). Discharge, ‘Q’ Vs Input power,

iii). Discharge, ‘Q’ Vs ηoverall

Result: -

Table for Observations: -

Table: 1Sl.

No.

Delivery head pressure, P in

kg/cm2

Suction

head

(Vacuum),

Pv in mm of

Hg

Time taken for 10

rev. of Energy

meter reading, ‘t’

sec.

Height of

water

collected,

h in mm

Disch

arge

time

in sec

Stage

-I

Stage-

II

Stage-

III

Stage-IV

Table for Calculations: -

Table: 2Sl.

No.

Head, H in

meters

Rate of discharge in

m3/s

H.Pelec (No

load)

H.Ppump ηpump H.Poverall

Expected Graphs: -

H Vs Q

P Vs Q

ηpumpVsQ

Q