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LMCIV206: Unified Lab-I

1

LABORATORY MANUAL

CIV206

Unified Lab-I

Table of Contents:

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Table of Contents

S.No. Title of the Experiment Page No.

1 To determine the workability of concrete by Slump test. 3-4

2 To determine the workability of freshly mixed concrete bycompaction factor test.

5-6

3 To determine normal consistency and setting time of thecement.

7-9

4 To determine the compressive strength of the cementconcrete cubes

10-11

5 To determine bulking of sand. 12-13

6 To determine the specific gravity of cement. 14-15

7 To determine water absorption and compressive strength of

bricks.

16-18

8 To determine the Meta centric height of a floating vesselunder loaded and unloaded conditions.

19-20

9 To verify Bernoullis equation experimentally. 21-22

10 To determine the coefficient of discharge for an obstructionflow meter (venturimeter/orifice meter)

23-24

11 To measure the velocity of flow at different points in a pipe. 25-26

12 To determine loss co-efficient for the pipe-fittings. 27-29

13 To study the transition from laminar to turbulent flow and toascertain the lower Critical Reynolds number.

30-32

14 To determine the discharge coefficient for a Vee notch or

rectangular notch.

33-35

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1. Title: To determine the workability of concrete by Slump test.

Equipment Required: Mould, pan, trowel weighing balance weight steel rod, Cone

(Bottom diameter 20 cm, Top diameter -10 cm, Height -30 cm)Material Required: Fine and coarse aggregate, cement, water.

Learning Objectives:

Unsupported fresh concrete, flows to the sides and a sinking in height takesplace. This vertical settlement is called slump. Slump increases as water

content is increased. Slump is a measure of workability or consistency of the

concrete. It gives us an idea of water content needed for concrete to be used

for different works. A concrete is said to be workable if it can be easily placed,

compacted, mixed and finished. A workable concrete should not show any

segregation and bleeding.

Slump Cone Apparatus

Procedure:

Prepare concrete mix with known proportions.

Place the mould on a smooth flat and non absorbent surface.

Fill the mould with concrete to about 1/4th the height.

Compact the concrete with the help of steal rod 0.6m long and 16mm in

diameter.

Fill the mould to about of its height and compact it again.

Repeat the procedure till the mould is filled completely and excess concrete is

trimmed off.

Remove the slump cone carefully in the vertical direction and on the removal

of the mould the concrete subsides.

Measure the height of concrete after subsidence.

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Scope of the results expected:

Water Cement ratio Slump

0.50

0.60

0.70

Result: The slump value of given concrete mix is found to be__

Cautions:

Make sure that the slump apparatus should be cleaned properly before

experiment.

Tamper the rod to the various places while compacting the concrete.

Use at least the number of blows as stated in experiment.

Observe the slump carefully.

Take the correct and accurate readings.

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2. Title: To determine the workability of freshly mixed concrete by compactionfactor test.

Experiment Required: Compaction factor testing machine hand weight andmachine weight.

Material Required: Cement, sand, coarse aggregate.

Learning Objective:

To test the workability of freshly concrete, compaction factor test is carried out. This

test works on the principal of determining the degree of compaction achieved by

standard amount of work done by allowing the concrete to fall through a standard

height the degree of compaction factor is the ratio of weight partially compacted

concrete to the wt of fully compacted concrete

Compaction Factor Apparatus

Procedure:

Prepare the dry concrete mix in the ratio 1:2:4 (kg cement ) Add water assuming the water ratio to be 0.65 (for 2kg of cement add 910 ml

at water)

Place the concrete mix in the upper hopper of the compaction Factor

apparatus and up the top level acierates

Open the trap in cylinder

Again open the trap in cylinder

Take the wt of cylinder concrete Compaction

Remove the concrete and refill the cylinder in three layers and give 25 blows

on each layer by tamping rod.

Again take the weight of cylinder with concrete and record it as weight of full

compacted concrete and calculate the compaction factor.

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S.No. Water cementratio

Mass withpartiallyfilledconcrete,W3

Mass withfullycompactedconcreteW3

Mass ofpartiallycompactedconcreteW2 W1

Mass offullycompactedconcreteW3 W1

1 0.5

2 0.6

3 0.7

4 0.8

The compaction for given concrete mix is found to be

Cautions:

Clean the apparatus before experiment.

Shift the lever gently.

Prepare the dry mix till uniformity of colour appears.

Make sure the bottom cylinder is firmly attached.

Weigh the concrete accurately.

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3. Title: To determine normal consistency and setting time of the cement.

Experiment Required: Vicat apparatus with Vicat plunger, Vicat needle and Vicat

mould, gauging trowel, measuring jar (100 to 200ml capacity), weighing balance

(accuracy 0.05 per cent of W), stop watch, rice plates, weight box, rubber gloves and

glass plates.

Material Required: Cement, Water.

Learning Objective:

Standard consistency is to find out the amount of water to be added to cement

to get a paste of normal consistency i.e the paste of a certain standard

solidity, which is used to fix the quantity of water to be mixed in cement before

performing tests for setting time, soundness and compressive strength.

In order the concrete may be placed in position conveniently, it is necessary

that the initial setting time of the cement should not too quick and after it has

been laid, hardening should be rapid so that the structure can be made od as

early as possible. The initial set is the stage after which any crack if appears

will not be reunited. The concrete is finally to be set when it has obtained

sufficient strength and hardness. Therefore certain limits for initial and final

setting time should be specified.

Vicat Apparatus

Procedure

(A) Standard Consistency

The standard consistency of a cement paste is that which permits the Vicat

plunger A to penetrate to a height 5 to 7 mm from the bottom of the Vicat

mould when the cement paste is tested as described below.

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For preparing one mould take for 00gm of cement passing 850- micron is

sieve and a pasts of cement with a weighed quantity of water (100ml) taking

care that the time of gauging is between 3 to 5 min. The gauging time is

counted from the time of adding water to the dry cement until commencing to

fill the mould.

Fill the Vicat mould resting upon non-porous plate with this paste. After

completely filling the mould smooth of the surface of the paste by single

movement of palm miffing it level with the top of the mould. The mould many

be slightly shaken to expel air.

Place the test block in mould with the non-pours resting plate under the rod

attached with the plunger A. Lower the plunger gently to touch the surface of

the test block and release it quickly, allowing it to sink into the paste.

Prepare the trial pastes with varying % of water (firstly at an interval of 4%, at

is of 24%, 28% and 32% and then at an interval of 1% and 0.25% between %

range determined by the previous test) and test as describe above until the

amount of water necessary for the standard consistency as defined is

obtained.

(B)Setting times of cement

Prepare a neat cement paste by gauging by the cement with 0.85 P water,

where P = standard consistency as found before. The gauging time is again

kept between 3 to 5 min. Start the stop watch at the instant when the water is

added to the cement.

Fill the Vicat mould and smooth off the surface of the paste making it level

with the top of the mould. The cement block thus prepared is known as test

block.

For the determine of initial setting time, place the test block confined in the

mould and resting on non-porous plates under the rod attached with the

needle B, lower the needle gently in contact with the surface of the test block

and release quickly, allowing it to penetrate into test block.


1. Percentage of water

2. Initial reading

3. Final reading

4. Height not penetrated, mm

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Mass of cement taken : 400 grams

Mass of water taken = 0.85 x P x 400 grams

1.Time in minutes

2.Initial reading3.Final reading

4.Height not penetrated, mm

Cautions:

The experiment should be conducted at a room temperature of 27+ 2 cent

grate and at a relative humidity of 90 per cent.

After a half min. from the instant of adding water, it should be thoroughly

mixed with fingers for at lest one min. A ball of this paste is prepared and thenit is present into the test mould, mounted on the non-porous plates.

The plunger are should be released quickly without pressure jerk, after the rod

is brought down to touch the surface of the test block.

For each repetition of the experiment fresh cement is to be taken.

Plunger should be cleaned during every repetition and make sure that it

moves freely and that there are non vibrations.

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4. Title: To determine the compressive strength of the cement concrete cubes.

Experiment required: 150mm cube moulds, CTM, buckets, trowel, and tray.

Material required: Cement, sand, coarse aggregate, water.

Learning objective:

To know the strength of the concrete in compression. The strength in compression

has its relationship with all other properties of concrete i.e. these properties areimproved with the improvement in the compressive strength.

Procedure:

Calculation of the material required: For preparing the concrete for given

proportions (1:2:4) by mass and water cement ratio of 0.6, take 3 kg of

cement, 6kg of fine aggregate and 12 kg of coarse aggregate. And 0.6% of

the total mass of cement.

Mix them thoroughly in the mechanical mixer until uniform colour of concrete

is obtained. If mixed with hand then care is to be taken that firstly mix the

cement and fine aggregate until the uniform colour of mixture is obtained.

Then the coarse aggregate is mixed with the above mixture until the proper

mix is in place. Then the required water as per calculation is to be added until

the uniform colour of mix of concrete is obtained. Mix for at least 2 minutes.

Take at least 3 moulds to be tested on three days for 7th, 14th and 28th day.

Pour the concrete in the moulds oiled with medium viscosity oil. Fill the

concrete in the moulds in three almost equal layers and each layer is to be

tampered at least with 35 blows with the help of tempering rod.

Struck off the concrete flush with the top of the moulds.

Immediately after being made, they should be covered with wet mats.

Specimen is to be removed from the moulds after 24 hours and to be

preserved in the water bath for 7, 14 and 28 days.

Compression tests of cube are made as soon as after removal of the cubes

from water bath.

Place the specimen carefully on the marks on the CTM and load is applied

continuously, uniform and without shock. The load is increased until the

specimen fails and record the maximum load carried by the each specimen

during the test.

a. Cube strength =

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On 7th day

Specimen No. 1 2 3 Average Strength,N/mm2

Load on cubes, KN

On 14th day


Load on cubes, KN

On 28th day


Load on cubes, KN

Cautions:

Both the mould and base plate should be lightly oiled before use to prevent

the concrete from sticking to the moulds.

The blows should be evenly distributed over the surface of each layer.

The moulds should be slightly overfilled after compacting, and then flushed /

struck off the upper part of the surplus to as to have the proper sized

specimen.

On no account must the specimens be allowed to dry, even partially and they

must be tested in wet condition.

Cube should be carefully placed on the CTM on the marks only.

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5. Title: To determine bulking of sand.

Apparatus: Balance, cylindrical container, graduated cylinder, beaker, metal tray,

steel rule and oven.

Learning objective:

1. To know the difficulty with the measurement of fine aggregate by volume

which has the tendency to vary in bulk according to moisture content. If sand

is measured by volume and no allowance is made for bulking, the mix will be

richer than that specified because for given mass, moist sand occupies

considerably larger volume than the same mass of dry sand.

2. If the sand is measured by loose volume, than it is necessary to increase the

measured volume of the sand in order that the amount of sand put into

concrete is intended for the nominal mix.

Procedure:

Put sufficient quantity of the oven dry sand loosely into the container until it is

about two-third full. Level off the top of sand and weigh the container.

Calculate the mass of sand by deducing the mass of the container.

Push the steel rule vertically down through the sand at the middle to the

bottom and measure the height of sand. Let it be hmm.

Empty the sand out into a clan metal tray without any loss.

Add one percent of water by mass of sand. Mix the sand and water thoroughly

by hand.

Put the wet sand loosely into the container without tamping it.

Smooth and level the top surface of the moist sand and measure its depth at

the middle with the steel rule. Let it e h mm.

Repeat the steps 4 to 6 of the above procedure with 2 % of water by mass.

Go on increasing the percentage by one till bulking is maximum and start

falling down and ultimate bilking is zero i.e saturated sand occupies the same

volume as dry sand.

Observation and calculation:

Material DetailsMass of container with oven dry sand,gmMass of empty container, gmMass of the fine aggregates, gmHeight of dry sand h,mm

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Mass of sand Mass of addedwater

Totalpercentage

Height ofsand hmm

Bulking= h-h/percentageX100

Precautions:

1. There should not be any inadvertent loss of sample.

2. Water should be measured accurately.

3. Container should be clean and dry.

Result Analysis:

Increase in bulking from 15 to 30 percent will result into an increase in concrete

strength by as much as 13 per cent. If no allowance is made for bulking concrete

strength may vary by as much as 25 percent.

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6. Title: To determine the specific gravity of cement.

Experiment Required: Weighting balance, Le-Chatelier flask, kerosene free from

water, specific gravity bottle, constant temperature water bath etc.

Material Required: Cement, distilled water, kerosene.

Learning Objective:

Specific gravity is normally defined as the ratio between the mass of a given

volume of material and mass of an equal volume of water. One of the

methods of determining the specific gravity of cement is by the use of a liquid

such as water-free kerosene which does not react with cement. A specific

gravity bottle may be employed or a standard Le-Chatelier flask may be used.

Procedure:

Weight the specific gravity bottle dry. Let the mass of empty bottle be W1.

Fill the bottle with distilled water and weight the bottle filled with water. Let the

mass be W2.

Wipe dry the specific gravity bottle and fill it with kerosene and weight. Let this

mass be W3.

Pour some of the kerosene out and introduce a weight quantity of cement

(about 50 grams) into the bottle. Roll the bottle gently in inclined position until

on further air bubbles rise to surface. Fill the bottle to the top with kerosene

and weigh it. Let this mass be W4.

From these data calculate the specific gravity of the cement.


1.Mass of empty bottle W1,gm

2. Mass of bottle +water W2,gm

3. Mass of bottle +kerosene W3,gm4. Mass of cement W5,gm5. Mass of bottle + cement + kerosene W4,gm

6. Sp. Gr. Of kerosene ,

s

7. sp. Gr. Of cement ,

S

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Cautions:

The kerosene used should be free from water

Clean the bottle before experiment.

While adding cement, care should be taken to avoid splashing and cement

should not adhere to the inside of the flask above the liquid.

Specific gravity bottle should be kept at optimum temperature.

Weigh the cement accurately.

Mix the mixture carefully.

Calculate the specific gravity to the nearest two decimals.

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7. Title: To determine water absorption and compressive strength of bricks.

Apparatus Required: 3 bricks, a sensitive balance capable of weighing within 0.1%

of the mass of the specimen and ventilated oven.

Procedure:

Dry the specimen in a ventilated oven at a temperature of 105 C to 115C till

it attains substantially constant mass.

Cool the specimen to room temperature and obtain its weight ( ) specimen

too warm to touch shall not be used for this purpose.

Immerse completely dried specimen in clean water at a temperature of

27+2C for 24 hours.

Remove the specimen and wipe out any traces of water with damp cloth and

weigh the specimen after it has been removed from water ( ).

CALCULATIONS

Water absorption, % by mass, after 24 hours immersion in cold water in given by the

formula,

The average of result shall be reported.

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Result

Water absorption of the givenbricks= .%

When tested as above, the average water absorption shall not be more than 20% by

weight up to class 12.5 and 15% by weight for higher class.

II) Title: to determine the compressive strength of bricks

Apparatus: Compression testing machine and bricks.

Sampling

Remove unevenness observed the bed faces to provide two smooth parallel faces

by grinding .Immerse in water at room temperature for 24 hours .Remove thespecimen and drain out any surplus moisture at room temperature. Fill the frog and

all voids in the bed faces flush with cement mortar (1 cement, 1 clean coarse sand of

grade 3mm and down). Store it under the damp jute bags for 24 hours filled by

immersion in clean water for 3 days .Remove and wipe out any traces of moisture.

Procedure

Place the specimen with flat face s horizontal and mortar filled face facing

upwards between plates of the testing machine.

Apply load axially at a uniform rate of 14 ( ) per minute till

failure occurs and note maximum load at failure.

The load at failure is maximum load at which the specimen fails to produce

any further increase in the indicator reading on the testing machine.

Calculation

The average of result shall be reported.

Range Calculation

Maximum compressive strength =

Contact area =

Maximum expected load =
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The range to be selected is

Result

Average compressive strength of the given bricks =..

IS SPECICATIONS

Speciation of Common Clay Building Bricks

Dimensions: The standard size of clay bricks shall be as follows

Length (mm) Width (mm) Height

(mm)

190 90 90

190 90 40

Classification: The common burnt clay shall be classified on the basis of averagecompressive strength as given in table.

Class Designation Average compressivestrength

Not lessthan

( )

Less than

( )

350 35 40

300 30 35

250 25 30

200 20 25

175 17.5 20

150 15 17.5

125 12.5 15

100 10 12.5

75 7.5 10

50 5 7.5

35 3.5 5
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8.Title: To determine the Meta centric height of a floating vessel under loadedand unloaded conditions.

Equipment required: Meta centric height apparatus.

Procedure:

Make the tank free from dust.

Fill tank with clean water and ensure that no foreign particles are there.

Weigh the ship model to find W.

Float the ship model in water and ensure that it is in stable equilbrium.

Apply the known weight (w) at the centre of model.

Give the model a small angular displacement in clock wise direction.

Measure the distance moved by the weight applied with the help of scale.

Measure the angle of tilt on the graduated arc.

Repeat the experiment for different weights.

Calculation Table:

S.No w (kg) W (Kg) X (cm) (Degree) Metacentricheight GM

123456

Standard Data:

Distance of grooves nos. 1,2,3,4,5 from centre= 2.5 cm, 5 cm, 7.5 cm, 10 cm, 12.5

cm.

Weight of ship model= 5.9 Kg

Weight of big strip= 2.6 Kg

Weight of small strip= 1.25 Kg (2 Nos)

Weight of hanger=110 Kg

Applied weights= 350 gm (1 No.), 500 gm (1 No.)

Formulae:

Meta Centric height GM= wx/ W tan

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G= Centre of gravity of the vessel

M= Meta centre of the vessel

w= applied weight

x= distance moved by weight w

W= weight of vessel including weight w.

= angle of tilt

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9. Title:To verify Bernoullis equation experimentally.

Equipmet required: Bernoullis apparatus, power supply: single phase, 220 Volt, 50hZ, and water supply.

Procedure:

Clean the apparatus and make the tanks free from dust.

Close the drain valves provided.

Fill sump tank with clean water and ensure that no foreign particles are

there.

Close flow control valve given at the end of test section.

Open flow control valve and by pass valve given on the water supply line to

overhead tank.

Ensure that all on/off switches given on the panel are at off position.

Now switch on the main power supply.

Switch on the pump.

Regulate flow of water through test section with the help of given gate valve at

the end of test section.

Measure flow rate using measuring tank and stop watch.

Observation table:

S.No R (cm)[rise of water level inmeasuring tank]

T(sec) H (cm)1 2 3 4 5 6 7 8 9

1

23

Calculation Table:

Run No=

Discharge= m3/s

TubeNo

1 2 3 4 5 6 7 8 9

V(m/s)p/g=hV2/2gZE

Precaution and maintenance Instruction:

Do not run the pump at low voltage i.e. less than 180 volts.

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Never fully close the delivery line and by passs line valves simultaneously.

Always keep apparatus free from dust.

To prevent clogging of moving parts, run pump at least once in a fortnight.

Always use clean water.

If apparatus will not in use for more than one month, drain the apparatus

completely and fill pump with cutting oil.

Standard data:

g = Acceleration due to gravity = 9.81 m/s2

A= Area of, measuring Tank = 0.1 m2

Formulae:

1. Total Energy (E):

E= (p/g) + (V2/2g) +Z

2. Velocity of fluid (V):

V= Q/a

3. Discharge (Q):

Q= v/t (v= A xR)

4. p/g = h

Where:

E = Total Energy

p/g = Pressure energy per unit weight of fluid or pressure head.

V2/2g = kinetic energy per unit weight of kinetic head.

Z= potential energy per unit weight of potential head.

p = Pressure of fluid (m of water).

V= Velocity of fluid (m/s)

Q= Discharge through test section

v = volume o water collected in measuring tank.

R = Rise of water level in measuring tank.

t = time taken for R

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10. Title:To determine the coefficient of discharge for an obstruction flowmeter (venturimeter/orifice meter)

Apparatus :-The apparatus consists of a Venturi meter, and Orifice meter fitted in pipeline.

The pipeline is taken out from a common inlet. At the downstream end of the

pipeline. Separate control valves are provided to regulate the flow through the

Venturimeter and orifice meter to conduct experiment separately. Pressure tapings

are taken out from inlet and throat of Venturi meter, inlet and outlet of Orifice meter

and are connected to a differential manometer. Discharge is measured with the help

of measuring tank and stop watch.

Learning objective:- To determine the co-efficient of discharge through Venturi meter & Orifice meter.

To compare the discharge of the venturi meter and orifice meter

Outline of the procedure:-Switch on the Pump and Operate the Flow Control Valve to regulate the flow

of water in the desired Test Section. Open the Pressure Taps of Manometer of

related Test section very slowly to avoid the blow of water on manometer fluid. Now

open the Air release Valve provided on the Manometer Slowly to release the air in

Manometer. When there is no air in the manometer, close the Air release valves.

Adjust water flow rate in desired with the help of control valve. Record the

Manometer reading. Measure the flow of water, discharge through desired test

section using stop watch and Measuring Tank. Repeat the same procedure for

different flow rates of water operating Control valve and By-Pass valve. When

experiment is over for one desired test section, open the By-pass Valve fully then

close the flow control valve of running test section and open the Control valve of

second desired test section and Repeat the same procedure for other test section.

Scope of Result and discussion:-

Parameters:-

To calculate the theoretical and actual discharge through a venturi meter and orifice

meter and hence find out the coefficient of discharge.

For Orifice meter:Theoretical discharge (Qt):

Qth = a1a2 2gH H = 12.6 x ha1

2 a22

Actual discharge (Qa): Co- efficient of discharge (Cd):Qa = A x R Cd = Qa/Qt

t

DATA:A = 0.1 m2

s = Specific gravity of Hg = 13.6

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g = Acceleration due to gravity = 9.81 m/sec2For Orificemeter:d1 = Dia inlet of Orificemeter = 25 mmd2 = Dia. of Orificemeter Plate = 15 mma1= d1

2 /4 Area at Inlet of Orificemeter =a2= d

2 /4 Area of Orifice Plate =

Where

H = 12.6 x h

h = Pressure difference in m of Hg.

A = Area of Measuring Tank (m2)

R = Rise of Water level in Measuring Tank (m)

t = Time taken for Rise of water level in measuring tank (sec.)

Qa = Actual discharge

Qt = Theoretical discharge

s = Specific gravity of Hg

PRECAUTION

Do not run the pump at low voltage i.e. less than 180 Volts.

Never fully close the Delivery line and By-Pass line Valves simultaneously.

Always keep apparatus free from dust.

To prevent closing of moving parts, Run Pump at least once in a fortnight.

Frequently Grease/oil the rotating parts, once in three months.

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11.Title: To measure the velocity of flow at different points in a pipe.

Apparatus:-

Complete set up of Pitot tube apparatus

Stop Watch

The pitot tube consists of a capillary tube, bent at right angle. The lower end, whichis bent through 90 is directed in the up stream direction. The liquid rises up in the

tube due to conversion of kinetic energy into pressure energy. The velocity is

determined by measuring the rise of liquid in the tube.

Learning objective:-

To find the co-efficient of pitot tube

To find the point velocity at the centre of a tube for different flow rates

To plot velocity profile across the cross section of pipe

Out line of procedure :-

Switch on the Main Power Supply (220 Volts AC, 50 Hz).Switch on the Pump.

Operate the Flow Control Valve to regulate the flow of water in the Test Section.

Open the Pressure Taps of Manometer of related Test section very slowly to avoid

the blow of water on manometer fluid. Now open the Air release Valve provided on

the Manometer Slowly to release the air in Manometer. When there is no air in the

manometer, close the Air release valves. Adjust water flow rate in desired with the

help of control valve.Set the Pitot tube at the centre of the Test section. Record the

Manometer reading.Measure the flow of water, discharge through desired test

section using stop watch and MeasuringTank. Now move the Pitot tube up & downon the same flow and note down the manometer readings tofind out the velocity at

different points in pipe. Repeat the same procedure for different flow rates of water

operating Control valve and By-Pass valve.

Scope of result and discussion:-ParametersCalculate velocity at various points by moving the pitot tube UP & down calculatecoefficient of pitot tube.

Plots :- Plot velocity profile

FORMULAE:Discharge (Q): Velocity,Q = A x R V = Q/a (m/s)

tActual Velocity = Cv 2 g H m/sH = 12.6 x h

Coefficient of Pitot Tube,

Cv = Q

a * 2 g H

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DATA:

A = Area of measuring tank = 0.1 m2

a = Cross section area of test section/pipe = 13.6

g = Acceleration due to gravity =

9.81 m/sec2

m = Density of manometer fluidw = Density of waterh = Manometer difference.

A = Area of Measuring Tank (m2)

R = Rise of Water level in Measuring Tank (m)

t = Time taken for Rise of water level in measuring tank (sec.)

Cv = Coefficient of Pitot Tube

a = Cross section area of Test Section

PRECAUTION

1. Do not run the pump at low voltage i.e. less than 180 Volts.

2. Never fully close the Delivery line and By-Pass line Valves simultaneously.

3. Always keep apparatus free from dust.

4. To prevent closing of moving parts, Run Pump at least once in a fortnight.

5. Frequently Grease/oil the rotating parts, once in three months.

6. Always use clean water.

7. It apparatus will not in use for more than one month, drain the apparatus

completely.

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12. Title: To determine loss co-efficient for the pipe-fittings.Apparatus: - Pipe fitting set up ,Stop watch

The apparatus consist of a bend and elbow, a sudden expansion from to Isudden contraction from I to and ball valve and gate valve. Pressuretapings are provided at inlet and outlet of these fittings at suitable distance. A

differential manometer fitted in the line gives pressure loss due to fittings. Supply tothe pipeline is made through centrifugal pump, which deliver water from sump tank.

The flow of water in pipeline is regulated by means of Control valve & By-Pass valve.

Discharge is measured with the help of measuring tank and stop watch.

Learning Objective: To determine the loss of head in the pipe fittings at the various water flow

rates.

To study various types of pipe fittings.

OUT LINE OF PROCEDURE:

Operate the Flow Control Valve to regulate the flow of water in the desired

test Section. Open the Pressure Taps of Manometer of related Test Section Very

slowly to avoid the blow of water on manometer fluid. Now open the Air release

Valve provided on the Manometer. Slowly to release the all in manometer. When

there is no air in the manometer. Close the Air release valves. Adjust water flow rate

in desired section with the help on Control Valve and record the Manometer reading.

Measure the flow of water, discharge through desired test section using Stop Watch

and Measuring Tank. Repeat same procedure for different flow rates of water.

Operating Control Valve and By-Pass valve. Repeat the above for each test section

separately .When experiment is over, close all Manometers Pressure Taps first,

Switch off Pump and Power Supply to Panel.

Formulaes:Loss of head due to change in cross-section, bends, elbows, valves and fittings of all

type fall into the category of minor losses in pipe lines. In long pipe lines the friction

losses are much larger than these minor losses and hence the latter are often

neglected. But in shorter pipelines thief consideration is necessary for the correct

estimate of losses. When there is any type of bend in pipe, the velocity of flowchanges, due to which the separation of the flow from the boundary and also

formation of eddies.Takes place. Thus the energy is lost.

The losses of head due to bend in pipe.hL= KL x V

22g

The minor losses in contraction can be expressed as:hL= KL x V1

2

2g

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The minor losses in enlargement can be expressed as:hL= KL x (V1-V2)

22g

WherehL= Minor loss or head loss

KL= Loss coefficient

V = Velocity of fluid.

V1= Velocity of fluid in pipe of small Diameter.

V2= Velocity of fluid in pipe of large Diameter.

Loss of Head (for Contraction):hL= KL x V1

22g

Loss Co-efficient:KL= hL x 2g

V12

Loss of Head (for Expansion):hL= KL x (V1-V2)

22g

Change of Kinetic Energy:

C = (V1-V2)22g

Discharge:

Q = Vt

Volume:v = A x R (m3)

Velocity:V1= Q (Velocity in Pipe)

a1

V2= Q (Velocity in 1 Pipe)a2

DATA:A = Area of the measuring tank = 0.1 m2

s = Specific gravity of Hg = 13.6

g = Acceleration due to gravity = 9.81 m/sec2

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Where

d1 = Dia of the smaller pipe =

d2= Dia of the larger pipe =

a1 = Area of Cross section of small dia. pipe =

a2 = Area of Cross section of large dia. pipe =

H = 12.6 x hV1= Velocity of fluid in pipe of Small Diameter (m).

V2= Velocity of fluid in pipe of Large Diameter (m).

V = Volume of water collected in measuring tank (m)

R = Rise of water level in measuring tank (m).

t = Time taken for R (sec.)

Scope of result and discussion:-

Parameters: - Find out the loss coefficient of Bend, Elbow, Ball valve ,gate valve

Differentiate between losses due to sudden enlargement and contractionPlots :- Nil

PRECAUTION & MAINTENANCE INSTRUCTIONS:

1. Do not run the pump at low voltage i.e. less-than 180 volts.

2. Never fully closed, the Delivery line and By-Pas line Valves simultaneously.


4. To prevent clogging of moving parts. Run Pump at least once in a fortnight.

5. Frequently Grease/Oil the rotating parts, once in three months.


7. It apparatus will not in use for more than one month drain the apparatus

completely.

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13. Title: To study the transition from laminar to turbulent flow and toascertain the lower Critical Reynolds number.

Apparatus: Reynolds Apparatus

Learning objective: To observe dye filament and identify laminar, turbulent or

transition flow

Procedure:

Clean the apparatus and make all the tanks free from dust.

Close the drain valves provided.

Fill sump tank with clean water and ensure that no foreign particles are there.

Close flow control valve given at the end of test section.

Open flow control valve and by pass valve given on the water supply line to

overhead tank.

Prepare a coloured solution one litre as dye i.e KMnO4 solution in clear water in

a separate vessel. Close the control valve for dye given in PU tubing. Put this

solution in dye vessel after ensuring that there are no foreign particles in

solution.


The water supply of the overhead tank should be maintained in such a way that

the over flow from it must be minimum. Otherwise greater turbulence will be

created in the overhead tank and the result will be affected badly.

Regulate minimum flow of water through test section with the help of given gate

valve at the end section. Then adjust the flow of dye through capillary tube so

that a fine colour thread is observed indicating laminar flow. Increase the flow

through glass tube and observe the colour thread, if it is still straight the flow still

remains to be in laminar region and if waviness starts it is the indication that the

flow is not laminar.

The discharge at the colour thread starts moving in wavy form, which

corresponds to higher critical Reynolds number and higher critical velocity.

Increase the discharge still further. The filament starts breaking up indicating

greater turbulence. Further increase in the discharge will cause the flow to be

turbulent which is apparent from the diffusion of the dye with the flowing water.

Now start decreasing the discharge first diffusion will continue. Further decrease

will decrease diffusion. If the discharge is further reduced, a stage will be

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reached when the dye filament become straight. This corresponds to lower

critical Reynolds number and lower critical velocity.

Measure flow rate using measuring cylinder and stop watch.

Standard data:

1. d = ID of glass tube = 25 mm = 0.0025 m

2. A= d2/4= cross sectional area of glass tube= .0.00049m2

3. = kinematic viscosity of water at 00 C= 1.788 x10-6 m2/s

200 C= 1.006 x10-6 m2/s

400 C=0.657 x10-6 m2/s

60

0

C=0.478 x10

-6

m

2

/sRe < 1800 for Laminar flow

Re> 2300 for Turbulent flow

Re= 1800-2300 is Transition zone

Formulae:

1. Re= Vd/

/ = Kinematic viscosity of fluid in m2/s

2. V= Q/A m/sec

3. Q= v/t in m3/s

Where

= Viscosity of fluid in N s/m2

= Density of fluid in kg/m3

V= Average velocity of fluid flow in m/sec.

v = volume of water collected in measuring cylinder m3

t= time taken for v

A= cross sectional area of glass tube

Observation Table

S.No v(ml) t (sec) Observation of the dye( type of

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flow)

1

2

3

4

5

Calculation Table:

S.No Q

m3/s

V

m/sec

Re= Vd/ Observation of thedye( type of flow)

1

2

3

4

5

Precautions:

1. Conduct the experiment when water will stable.

2. Do not run the pump at low voltage

3. Never fully close the delivery line and by-pass line valve simultaneously.


5. To prevent clogging of moving parts, run pump at least once in a fortnight.

6. Frequently grease/oil the rotating parts once in three months.


8. If apparatus will not in use for more than one month, drain the apparatuscompletely and fill pump with cutting oil.

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14. Title: To determine the discharge coefficient for a Vee notch or

rectangular notch.

Apparatus: Discharge over notches.

Learning objective:To make flow measurement calculations

Procedure:

Clean the apparatus and make all three tanks free from dust.

Close the drain valve provided.

Close flow control valve given in water line.

Open by-pass valve.

Fix desired notch on the flow channel.

Fill sump tank with clean water and ensure that no foreign particles arethere.

Ensure that all on/off switches given on the panel are at off position.


Regulate flow of water through channel with the help of given flow controlvalve.

Record the height of water level in the channel with the help of pointergauge.

Measure flow rate using measuring tank and stop watch

Standard data

Rectangular notch

Width = 50 mm

Depth= 80 mm

V-Notch

Depth =80 mm

Angle of notch = 450 and 600

Area of measuring tank= 0.099647m2

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Formulae

Discharge over a rectangular notch:

Q= 2/3 CdL 2g [H]3/2

Discharge over a V notch:

Q= 8/15 Cd tan/2 2g [H]5/2

Volume V= R x A (m3)

Actual Discharge Qactual = V/t (m3/sec)

Cd= actual discharge/ theortical discharge

Q= actual discharge in m3/sec

Cd= Co-efficient of discharge

L= width of the rectangular notch in meter

= angle of V-notch

g = acceleration due to gravity in m/s2

H= water head over crest in meter

A= area of measuring tank in m2

R= rise of water level in measuring tank in cm

V= volume of water in m3

t = time taken to R in sec

OBSERVATION TABLE:

S.No H (cm) R (cm) t (sec)

1

2

3

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CALCULATION TABLE:

S.No H (m) Q (m3 /s) Cd

1

2

3

Precautions:

1. Never switch on main power supply before ensuring that all the on/off

switches given on the panel are at off position.

2. Never run the pump at low voltage.

3. Never fully close the delivery and by-pass line valves simultaneously.


5. To prevent clogging of moving parts, run pump at least fortnight.

6. Frequently grease/oil the rotating parts once in three months.


8. If apparatus will not in use for more than one month, drain the apparatuscompletely and fill pump with cutting oil.

15398_civ206

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