Fluid Mechanics Lab Report PDF

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FluidMechanics Fluid MechanicsLab LabReport Report PreparedBy: Prepared By:Muhammad MuhammadBilal Bilal CivilEngineering Civil EngineeringDepartment, Department,Uet UetPeshawar Peshawar Fluid Mechanics Lab report Table of Contents Demonstration of various parts of hydraulic bench Lab 1 To determine ...

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FluidMechanics MechanicsLab LabReport Report Fluid PreparedBy: By:Muhammad MuhammadBilal Bilal Prepared CivilEngineering EngineeringDepartment, Department,Uet UetPeshawar Peshawar Civil

Fluid Mechanics

Lab report

Table of Contents

Demonstration of various parts of hydraulic bench

Lab 1

To determine the discharge and coefficient of Discharge over Lab 2 and 3 rectangular and triangular Notch Investigation of different types of flows Reynolds’s apparatus (by visual observation)

using Osborne Lab 4

Investigation of different types of flows using Osborne Reynolds’s apparatus (by Reynolds’s number formula)

Lab 5

To determine the theoretical and actual center of pressure on Lab 6 partially submerged body. To determine hydraulic co-efficient and to study jet profile of a small circular orifice provided at side of tank

Lab 7

To determine the hydraulic coefficients for a circular orifice at the bottom of tank

Lab 8

To investigate the velocity of Bernoulli’s theorem as applied to the Lab 9 flow of water by Bernoulli’s theorem demonstration To determine the relationship between head loss due to friction and Lab 10 velocity for flow of water through smooth bore pipe

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Fluid Mechanics

Lab Report

Experiment # 1 DEMONSTRATION OF VARIOUS PARTS OF HYDRAULIC BENCH Hydraulic bench is a very useful apparatus in hydraulics and fluid mechanics. It is involved in majority of experiments to be conducted e.g. to find the value of the co-efficient of velocity, CV, coefficient of discharge ' Cd, to study the characteristics of flow over notches, to, to find head losses through pipes, to verify Bernoulli's theorem etc.

Various Parts of hydraulic Bench SUMP TANK It stores water for Hydraulic bench. It is located in the bottom portion of Hydraulic bench. Water from here is transported to other parts by using a pump. It has a capacity of 160 liters

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VOLUMETRIC TANK It stores water coming from channel. This tank is stepped to accommodate low or high flow rates. It has a capacity of 46 liters

DUMP VALVE It is used for emptying volumetric tank. It is located in the bottom of the volumetric tank.

CHANNEL It is used in number of experiments it provides passage for water for different experiments. A valve is also attached to the channel to measure the depth of water in channel.

SIDE CHANNELS They are the upper sides of the channel. They are used to attach accessories on test

CENTRIFUGAL PUMP It draws water from sump tank and supplies it for performing experiments Vertical pipe it supplies water to the upper part of hydraulic bench from sump tank through a pump

CONTROL VALVE It is used to regulate the flow in the pipe i.e. to increase or decrease the inflow of water in the hydraulic bench

STILLING BAFFLE It decreases the turbulence of water coming from channel. It is located in the volumetric tank.

OVER FLOW It is an opening in the upper portion of the volumetric tank. It sends the water level above 46 liters to the sump tank

STARTER It on / off the hydraulic bench. CED, UET-P

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SCALE & TAPPING A sight tube and scale is connected to a tapping in the base of the volumetric tank and gives an instantaneous indication of water level.

ACTUATOR : Dump valve is operated by a remote actuator, lifting actuator opens the dump valve, when it is given a turn of 90' it will turn the dump valve in the open position

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Experiment # 2 and 3

TO DETERMINE THE DISCHARGE AND COEFFICIENT OF DISCHARGE OVER RECTANGULAR AND TRIANGULAR NOTCH.

Objectives of the Experiment: 1. To demonstrate the flow over different weir types. 2. To calculate the coefficient of discharge for different notch types.

Theory For the rectangular Notch:

And for triangular Notch

Where Cd = Coefficient of discharge B or L = width of the rectangular weir (3 cm) H = head above the Notch apex θ = angle of the triangular weir g = acceleration of gravity

Apparatus • Hydraulic bench • Stop watch CED, UET-P

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• Hook and point gauge • Notch plates

Experimental Setup

Procedures and Readings 1. Make sure that the Hydraulic Bench is levelled. 2. Consider the zeros in point gauge. Take enough care not Damage the weir plate and the point gauge 3. Put the point gauge half way between the stilling baffle plate and the Notch plate. 4. Allow water to flow into the experimental setup and adjust the Minimum flow rate by means of the control valve to have atmospheric Pressure all around water flowing over the Notch. Increase the flow rate incrementally such that the head above the weir crest increases around 1 cm for each flow rate increment. 5. For each flow rate, wait until steady condition is attained then measure and record the head (H) above the weir 5. For each flow rate, measure and record the initial and final volumes in the Collecting tank and the time required to collect that volume. For each Flow Rate, take 3 different readings of the volumes and time and record the average CED, UET-P

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Fluid Mechanics

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For the rectangular Notch:

Where b=width of notch 𝑸 = 𝒌 × 𝑯𝟑/𝟐 Equating both equations and taking log on both sides

This log equation is the equation of a line where logk is y intercept and slope n=3/2 Finally equation for Cd

V(dm^3)

time(sec)

Q(dm^3/sec)

H1

H2

H(dm)

logQ

LogH -

10

8.37

1.19474313

85

156

0.71

0.077275

10

10.21

0.979431929

85

146

0.61

-0.00903

5

11.31

0.442086649

85

122

0.37

-0.35449

0.14874 0.21467

-0.4318

After plotting we get the coefficient of x=1.525 which should be 1.5,

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Fluid Mechanics

Lab Report

For triangular notch:

Equating both equations and taking long on both sides

Finally equation becomes

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time(s)

Lab Report

Q(dm^3/

H1

H2

H(dm)

LogQ

LogH

s) 29.2

0.3425

125

158

0.33

-0.4654

-0.4815

36.98

0.2704

125

154

0.29

-0.5680

-0.5376

30.33

0.1649

125

150

0.25

-0.7829

-0.6021

Logk=0.8026

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Experiment # 04: Investigation of different types of flows using Osborne Reynolds’s apparatus (by visual observation). OBJECTIVE: The objective of this experiment is to determine different types of flows under different conditions visually.

Types of flows: There are three types of flows. S No.

Types of flow

Reynolds’s number

Remarks

1

Laminar flow

R4000

When stream line interact and complete mixing of flow occur. Dye stream completely disappear in flow of water. Figure 1 Reynolds’sOsborne Apparatus

APPRATUS: 1. Hydraulic bench 2. Osborne Reynolds’s apparatus 3. Dye 4. Thermometer

COMPONENTS OF OSBORNE REYNOLD’S APPRATUS. 1. Dye reservoir. 2. Control valve. 3. Over flow pipe. 4. Head tank. 9. Velocity control valve.

5. Bell mouth inlet 6. Marbles. 7. Water supply pipe. 8. Flow visualization pipe.

Fluid Mechanics

Lab report

Dye Reservoir Control Over flow

Head

Needle Marble pieces

Flow visualization pipe

Velocity control valve Water supply pipe

Osborne Reynolds' Apparatus

PROCEDURE: • Fill the reservoir with dye. • Fix the apparatus on the bench and connect the inlet water supply pipe with the bench feet.

• Lower the dye injector until it’s just above the bell mouth inlet. • Open the bench inlet valve and slowly fill the head tank up to the overflow level. And • • • •

then close it. Open the velocity control valve to enter water to the flow visualization pipe. Open the control valve slightly and adjust the dye control valve until slow flow with thin dye line is obtained (laminar flow). Increase the flow rate till the dye takes a wave form (transition flow). Further increase of flow rate will completely disappear the dye and form eddies (turbulent flow).

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Different Flows

OBSERVATION AND CALCULATIONS S.NO

OBSERVATION

TYPE OF FLOW

1

DYE CANNOT MIX WITH WATER AND MOVE PARRALLEL

LAMINAR

2

DYE PARTIALLY MIX WITH WATER

TRANSITION

3

DYE COMPLETELY DISAPPEAR IN WATER

TURBULANT

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Experiment # 05 Investigation of different types of flows using Osborne Reynolds’s apparatus (by Reynolds’s number formula) OBJECTIVE: The objective of this experiment is to determine different types of flows under different conditions by Reynolds’s number formula.

Where: R=Reynolds number V=velocity of fluid ϑ =Kinematic viscosity at observed temperature of water.

APPRATUS: 1. Hydraulic bench 2. Osborne Reynolds’s apparatus 3. Dye 4. Thermometer

PROCEDURE: • Fill the reservoir with dye. • Fix the apparatus on the bench and connect the inlet water supply pipe with the bench feet.

• Lower the dye injector until it’s just above the bell mouth inlet. • Open the bench inlet valve and slowly fill the head tank up to the overflow level. And • • • • •

then close it. Open the velocity control valve to enter water to the flow visualization pipe. Open the control valve slightly and adjust the dye control valve until slow flow with thin dye line is obtained (laminar flow). Note down the volume and time using graduated cylinder and stop watch. Increase the flow rate till the dye takes a wave form (transition flow).and record volume and time. Further increase of flow rate will completely disappear the dye and form eddies (turbulent flow).again calculate volume and time for this flow.

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OBSERVATION AND CALCULATION

VOLUME (M3)

TIME (S)

TEMP (C)

3

Q(m /s)

Velocity =Q/A (m/s)

ϑ

R

Type of flow

2x10-4

110.54

20°C

1.809x10-6

0.023

1.003x10-6

229.3

laminar

3x10-4

70.6

20°C

4.249 x10-6

0.054

1.003x10-6

538.4

laminar

8x10-4

31.7

20°C

2.525 x10-5

0.322

1.003x10-6

3210

transition

4x10-4

77.57

20°C

5.157 x10-5

0.657

1.003x10-6

6550

turbulent

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Lab report

Experiment No 06: To determine the theoretical and actual center of pressure on partially submerged body. Objective: The objective of this experiment is to determine the hydrostatic thrust acting on a plane surface immersed in water.

Theory: Thrust force is given by.

Theoretical center is given by.

Actual center is given by.

Where: W=weight P=moment arm (p=27.5cm) 𝐹𝑟=resultant force R=depth of water Q=depth of water from pivot point (q=20-r) B=width of plane area (B=7.5cm)

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Lab report

P

Q

W

R

Different Parts of Apparatus

Apparatus: 1. Hydraulic pressure apparatus 2. Weights 3. Water

Hydraulic pressure device.

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Procedure: 1. Position the empty hydrostatic apparatus on a plane table or hydrostatic bench and adjust the leveling screw until the circular spirit level shows that the base in horizontal and balance. 2. Then concede share edge of beam and y-line.by moving the counter balance weight. 3. Ensure that the drain valve is closed and the plastic pipe is connected to the drain valve. 4. Add 50g weight to the weight hanger. 5. Add water until the hydrostatic thrust on the end face of quadrant causes the balance arm to rise. 6. Continue adding water until balance arm is horizontal, measuring this by aligning the base of balance arm with the central marking on the balance rest. 7. If the tank is over filled then the equilibrium can be obtained by slightly opening the drained valve and allow some water to flow. 8. Read the depth of the immersion from the scale on the face of the quadrant. 9. Repeat the same procedure and increase the load by 50g each time. And take four readings.

Observation and calculation

S No

Weight (g)

Weight (n)

Depth of water R(m)

Q(m) Q=0.2r

𝐻𝑝 Actual

𝐻𝑝 Theoretical (m)

𝐹𝑟(n) (m)

(cm)

(m)

(cm)

1

50

0.49

0.046

0.154

0.778

0.173

17.3

0.184

18.4

2

100

0.98

0.066

0.134

1.602

0.168

16.8

0.178

17.8

3

150

1.47

0.083

0.117

2.534

0.159

15.9

0.172

17.2

4

200

1.96

0.097

0.103

3.461

0.156

15.6

0.168

16.8

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Experiment # 7 To determine hydraulic co-efficient (𝐶𝑑 ,𝐶𝑣, 𝐶𝑐) and to study jet profile of a small circular orifice provided at side of tank Theory • •

An orifice is an opening in a vessel through which water flows out, in case of orifice the upstream level of water is above the top edge of opening Co-efficient of contraction is the ratio of area of jet at vena contracta to the area of orifice Mathematically

•

Co-efficient of velocity is the ratio of actual velocity to the theoretical velocity of jet from orifice Mathematically Where ℎ𝑜 is depth of water over orifice (from center) and ℎ𝑐 is velocity head of jet at vena contracta. In this experiment we will find 𝐶𝑣 with the help of jet profile 𝐶𝑣 = √

•

𝑥2

4𝑦 ℎ 𝑜 i.e. Co-efficient of discharge is the ratio of actual discharge to theoretical discharge

Mathematically •

Vena contracta is the portion of jet with least diameter

• •

Diameter of orifice used in experiment is 6mm A jet is a stream of fluid that is projected into a surrounding medium, usually from some kind of a nozzle or orifice. Jets can travel long distances without dissipating, Jet profile refers to the trajectory followed by jet during the experiment.

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Apparatus Used in experiment

Fig 1- Labeled diagram of orifice and Jet apparatus

Fig 2- Actual apparatus (It is fitted over hydraulic bench and then the experiment is Performed)

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Procedure • • • • • • •

Adjust the orifice and jet apparatus over hydraulic bench, through control valve start flow and wait till there is reasonable amount of water in head tank Adjust the overflow accordingly and note the reading of overflow as ℎ𝑜 Water will comes out of orifice, Screw up the needles according to the path of the flow of water Mark the points of top of needle accurately by pencil on A3 size paper sheet. For specific volume of water that is been driven to volumetric tank find the time with help of stopwatch Remove the paper and find x and y distances with respect to a reference line/first point Plot y on x-axis and 𝑥2 on y-axis in Excel and calculate slope for 𝐶𝑣 From the data collected find the other co-efficient

Fig 3- Experimental setup over hydraulic bench and marking of points on A3 size paper

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Observations and calculations x (cm) 0 5 10 15 20 25 30 35

𝑥2 (cm) 0 25 100 225 400 625 900 1225

y (cm) 0 0.6 1.6 2.9 5 7.4 10.2 13

After plotting y and 𝑥 2 Values

X^2/y plot

1400 1200

y = 93.916x - 40.297

1000 800 600 400

200 0 0

2

-200

We get

4

6

8

10

12

14

Y values

93.916cm and we have, ℎ0=31cm 𝐶𝑣 = √

𝑥2 4𝑦 ℎ 𝑜

99.916

𝐶𝑣 =√ 4(31 ) 𝐶𝑣 = 0.87

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For 𝐶𝑑

From Experiment Diameter d of orifice=0.6cm, Area of orifice=0.283𝑐𝑚2 Take g=980cm/𝑠𝑒𝑐2 Volume=3litre=3000𝑐𝑚3 ℎ0=31cm Time=82.37sec 3000 ⁄82 .37 𝐶𝑑 = 0.283 √ 2(980 )(31 )

𝐶𝑑 =0.52 Now to calculate 𝐶𝑐 we know that

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Experiment # 8 To determine the hydraulic coefficients (𝐶𝑑 ,𝐶𝑣, 𝐶𝑐) for a circular orifice at the bottom of tank Theory •

•

An Orifice is an opening in the side or base of tank or reservoir through which fluid is discharge in the form of a jet. The discharge will depend up on the head of the fluid (H) above the level of the orifice. The term small orifice means that the diameter of the orifice is small compared with the head producing flow The equations for hydraulic coefficients are

• • •

Apparatus used in experiment

Fig 1- orifice at bottom of tan...