HYDRAULIC LABORATORY MANUAL

1st

Sem

este

r

2019/2020

Philadelphia University Faculty of Engineering

Civil Engineering Department

HYDRAULIC LABORATORY MANUAL

Prepared by Reviewed by Approved by

Eng.Isra’a Alsmadi Lab Instructor

Dr.Ahamad Dubdub Associate Professor

Dr.Mohmmed Al-Iessa Associate Professor Head of Civil Engineering Dept

2

Prepared by: Eng. Isra’a I. Al-Smadi

SYLLABUS

(Hydraulics Laboratory)

Course number and name 0670442: Hydraulics Laboratory

Credits and contact hours 1 Credit Hour

Instructor’s : Instructor: Eng.Isra’a Alsmadi and Eng.Esra’a Alhyasat

Text book, title, author, and year

“Hydraulics Laboratory Manual”, (Prepared Eng.Isra’a Alsmadi/ Civil Engineering

Department/Philadelphia University),(2019)

Specific course information

Brief description of the content of the course (catalog description)

Calibration of bourdon gauge, Metacentric height of floating bodies , Osborne

Reynolds demonstration , Impact of jet, Orifice and free jet flow determination of

coefficient of velocity and coefficient of discharge, Triangular and rectangular

notches and Hydraulic gradient with ground water flow.

Prerequisites

Prerequisite: Hydraulics (0670441)

Course objectives:

The students will be able to understand and follow procedures, through lab manual.

The students will be able to work in teams, as experiments are conducted in

groups.

The students will be able to prepare a technical report, as the findings of

experiments have to be reported in well-structured format.

The students will be able to critically evaluate their results, by comparing them

with related published information.

The Students will understand and be able to apply fundamental concepts and

techniques of hydraulics in the analysis, design, and operation of water resources

systems. The students will be able to appreciate how the theoretical concepts are applied

practically.

The students will be able to understand how results of a practical are influenced by

the status of the apparatus.

3


Course outcomes:

Students who successfully complete this course will have demonstrated ability to:

Identify, name, and characterize flow patterns and regimes.

Understand basic units of measurement, convert units, and appreciate their

magnitudes.

Measure volume flow rate and relate it to flow velocity

Use word and excel software in writing reports.

Compare the results of analytical models introduced in lecture to the actual

behavior of real fluid flows and draw correct and sustainable conclusions.

List of experiment:

Experiment (1): Calibration of Bourdon Gauge

Experiment (2): Metacentric Height of Floating Bodies

Experiment (3): Osborne Reynolds Demonstration

Experiment (4): Impact of Jet (I)

Experiment (5): Impact of Jet (II)

Experiment (6): Orifice and Free Jet Flow Determination of Coefficient of Velocity

Experiment (7): Orifice and Free Jet Flow Determination of Coefficient of Discharge

Experiment (8): Coefficient of Discharge for a Rectangular Notch

Experiment (9): Coefficient of Discharge for a Triangular Notch

Experiment (10): Hydraulic Gradient with Ground Water Flow

Evaluation

60 % Lab work [quizzes and lab reports]

40 % final Exam

Attendance and Course Policies

Absence: - two absences are allowed with accepted excuse and the experiments must be

recovered. Any exceeding for the permitted absences will be restricted from taking the

final exam

Reports: no late submission will be accepted. Missing reports will result in a zero grade.

Cheating is not tolerated. A student guilty of cheating will receive a zero grade. Cheating is

any form of copying of another student’s work, or allowing the copying of your own work.

The late on the lab time: - the student is allowed to enter the lab after 10 minutes from

the starting the lab only.

Discipline: any student make any disturbance in the lab will be dismissed immediately

Dismissing: no student is allowed to dismiss from the lab until the lab is finished for any

excuse.

Quizzes: - it is about the previous experiment and it is given at the end of each lab after

finishing the experiment

All cellular phones must be turned off before lab begins.

4


List of Experiments

Experiment (1): Calibration of Bourdon Gauge

Experiment (2):Metacentric Height of Floating Bodies

Experiment (3):Osborne Reynolds Demonstration

Experiment (4):Impact of Jet (I)

Experiment (5):Impact of Jet (II)

Experiment (6): Orifice and Free Jet Flow Determination of Coefficient of Velocity from Jet

Experiment (7): Orifice and Free Jet Flow Determination of Coefficient of Discharge from Jet

Experiment (8): Coefficient of Discharge for a Rectangular Notch

Experiment (9): Coefficient of Discharge For a Triangular Notch

Experiment (10): Hydraulic Gradient with Ground Water Flow

5


HOW TO WRITE A LAB REPORT?

LAB REPORT ESSENTIALS

1. Title Page

It would be a single page that states:

a. The title of the experiment.

b. Your name and the names of any lab partners.

c. Your instructor's name.

d. The date the lab was performed or the date the report was submitted.

2. Title

The title says what experiment you did.

3. Introduction / Purpose

Usually, the Introduction is one paragraph that explains the objectives or purpose of the

lab. Sometimes an introduction may contain background information, briefly summarize

how the experiment was performed, state the findings of the experiment, and list the

conclusions of the investigation. Even if you don't write a whole introduction, you need

to state the purpose of the experiment, or why you did it. This would be where you state

your hypothesis.

4. Materials

List everything needed to complete your experiment.

5. Methods or procedure

Describe the steps you completed during your investigation. This is your procedure. Be

sufficiently detailed that anyone could read this section and duplicate your experiment. Write it

as if you were giving direction for someone else to do the lab. It may be helpful to provide a

Figure to diagram your experimental setup.

6. Data and Results

Numerical data obtained from your procedure usually is presented as a table. Data encompasses

what you recorded when you conducted the experiment. It's just the facts, not any interpretation

of what they mean.

6


7. Discussion or Analysis

The Analysis section contains any calculations you made based on those numbers. This is where

you interpret the data and determine whether or not a hypothesis was accepted. This is also

where you would discuss any mistakes you might have made while conducting the investigation.

You may wish to describe ways the study might have been improved.

8. Conclusions

Most of the time the conclusion is a single paragraph that sums up what happened in the

experiment, whether your hypothesis was accepted or rejected, and what this means.

9. Figures & Graphs

Graphs and figures must both be labeled with a descriptive title. Label the axes on a graph,

being sure to include units of measurement.

10. References

If your research was based on someone else's work or if you cite facts that require

documentation, then you should list these references.

WHAT IS A SCATTER PLOT?

A scatter plot is a chart with points that show the relationship between two or more sets of data.

The data is plotted on the graph as Cartesian coordinates, also known as data on an X-Y scale.

7


FLOW RATE FORMULAS:

Volume flow rate:

The flow rate of a liquid is a measure of the volume of liquid that moves in a certain amount of time.

The flow rate depends on:

The area of the pipe or channel that the liquid is moving through

The velocity of the liquid

Note:

1 m3/s = 1000 L/s.

� = �� =�

�

Q = Volume flow rate (m3/s or L/s)

A = area of the pipe or channel (m2)

v = velocity of the liquid (m/s)

V=volume that passes through an area(m3 or L)

T=time(sec)

Mass flow rate: Mass Flow Rate is defined as the transfer of a mass of substance per unit of time. Mass flow rate can be

calculated from the density of the liquid (or gas), its velocity, and the cross sectional area of flow.

� = �� = � ∗ � = � ∗ � ∗ �

Where,

m = Q� = mass flow rate(Kg/s),

Q = Volume flow rate (m3/s or L/s)

A = area of the pipe or channel (m2)

v = velocity of the liquid (m/s)

ρ = �luid density (Kg/m�

8


Assignment:

1) Water is flowing through a circular pipe that has a radius of 0.0800 m. The velocity of the water

is 3.30 m/s. What is the flow rate of the water in liters per second (L/s)?

2) Water is flowing down an open rectangular chute. The chute is 1.20 m wide, and the depth of

water flowing in it is 0.200 m. The velocity of the water is 5.00 m/s. What is the flow rate of the

water through the chute in liters per second (L/s)?

3) Calculate the mass flow rate of liquid or gas by the given details.

Density of the liquid or gas (kg/m3) = 25

Velocity of the liquid or gas (m/s) = 20

Flow Area of the Liquid or gas (cm2) = 15

4) For the following plot draw the trend line and calculate its slope:

9


Laboratory Safety Requirements

الھیدرولیكالعامة في مختبر السلامة اءات ارجا

:اتلمختبرامشرفي ولطلبة التالیة من قبل العامة السلامة دئ ابمبالتقید ایجب

.لملابسوالیدین والسلامة للجسم العمل لتأمبن اء ارواب اتدرلطلبة باام الزورة اضر )1(

.لمختبراخل دالنقالة اتف الھوام استخدایمنع )2(

سمير عمل لمختبر لمن لیس لھاخل داجد التوایمنع )3(

ايلمختبر للعمل في ازیة ھجان ضمات وضیارلادوات والاوالمختبر اعلى نظافة ظ لحفاایجب )4(

.قتو

.هلانتبام اعد عن ناتجةادث یة حوع المختبر منعا لوقواخل دالركض اح او المزایمنع )5(

.ضلمراو التعب العمل في حالة ایمنع )6(

.لعملاي في حالة ة وھلاجھزایمنع تنظیف )7(

.لعملت الاواة وطلاجھزت واضیارلاالمحافظة على نظافة ایجب )8(

من ءلانتھاابعد ت لمضخاالتي یتطلب فیھا تشغیل ة الاجھزافي ت لمضخاء افااطلتاكد من ا )9( .ةلاجھزالك لتامین سلامة رب وذلتجاا

:ما یلية عاالمختبر مرس امھندف او لمشرا علىو

.لمختبردرة اقبل مغاه لمیات الكھربائي عن سخانار التیاالتاكد من فصل ا )1(

.درةلمغااقبل ء لماء والكھرباء افااطلتاكد من ا )2(

.مسبقاة لاجھزالتاكد من صلاحیة واا اؤھجري المنورب التجاة والمسبق للاجھزالتحضیر ایجب )3(

.لمختبرالي في ولاف اللاسعاوق یجب توفر صند )4(

للمختبر لرئیسيا بلباا من قریب نمكا في ضعھاوو لمختبرا في مناسبة حریق فایةط توفر یجب )5( .زلغات انااسطووالطاقة ارة والحردر اا عن مصادھبعاوا .لیھال الوصوالتسھیل

10


Experiment 1

CALIBRATION OF BOURDON GAUGE

INTRODUCTION:

The bourdon gauge is the most popular pressure measuring device for both liquids and

gasses. It can be connected to any source of pressure such as a pipe or vessel containing a

pressurized fluid. The connection can either be direct or via a small tube called a capillary

tube. This means that it can be mounted at any convenient location. It is also very

versatile in that it can be designed to operate over virtually any range of pressures. The

Bourdon gauge normally measures so called Gauge Pressure, which is the difference

between the pressure in the pressure source and the current atmospheric pressure. It can

however be modified to measure difference in pressure between two sources of pressure

(i.e. pressure difference or differential pressure). The Bourdon gauge is an indirect

measuring device which depends for its operation on the tendency of an internally

applied pressure to cause an initially bent tube (called a bourdon tube) to straighten.

Because the measurement is indirect it is necessary to calibrate the gauge before it can be

use.

The calibration consists of applying a known pressure to the gauge and noting the

position of the gauge needle on the scale. The gauge can be calibrated in a wide variety of

units to suit the particular application provided that there is a linear relationship between

actual pressure and the unit of calibration.

OBJECTIVE:

To perform pressure calibration on a Bourdon tube pressure gauge using a dead

weight tester.

To establish the calibration curve of the Bourdon Gauge

APPARATUS:

Bourdon Gauge and dead weight tester

Set of Test weights

Laboratory Scales

11


THEORY:

The use of the piston and weights with the cylinder generates a measurable reference

pressure, P:

� =�

�(��)

Where

� = ��

And

F: is the force applied to the liquid in the liquid in the calibrator

M: is the total mass (including that of the of the piston)

A: is the area of piston

The area of the piston can be expressed in terms of its diameter, d, as:

� =��

�

PROCEDURE:

The weight of the Piston, and its cross sectional area should be noted. To fill the cylinder,

the piston is removed, and water is poured into the cylinder until it is full to the overflow

level. Any air trapped in the tube may be cleared by tilting and gently tapping the

apparatus. In point of fact, a small amount of air left in the system will not affect the

experiment, unless there is so much as to cause the piston to bottom on the base of the

cylinder. The piston is then re-placed in the cylinder and allowed to settle. A spirit level

placed on the platform at the top of the piston may be used to ensure that that the cylinder

is vertically upright. Weights are now added in convenient increments, and at each

increment, the pressure gauge reading is observed. As similar set of results is then taken

with decreasing weights. To guard against the piston sticking in the cylinder, it is

advisable to rotate the piston gently while the pressure gauged is being read.

12


TABLE OF OBSERVATIONS AND CALCULATIONS:

All readings and calculations are to be tabulated as follows:

Data for the Piston:

Mass of the piston (Mp) = 498g ≈0.5Kg

Diameter of the piston (d) = 0.01767m

Relative Error = (Measured Value – Actual Value) /Actual Value

Percent Error = │Relative Error│ × 100

Note: Also, show the sample calculation to calculate the Relative Error and

Percent Error.

GRAPHICAL RELATIONSHIP:

Plot the following graphs:

Actual Pressure against Measured Pressure (Gauge Reading)

Percent Error against Measured Pressure (Gauge Reading)

CONCLUSION AND RECOMMENDATIONS:

Comment on the accuracy of the gauge.

Is the relative height between the calibrator and the gauge important in

calibration?

General comments about the experiment

Your recommendations

Area of

piston

A(m2)

Mass of

weights

Mw(Kg)

Gauge reading

G(kPa)

Cylinder

pressure

P( kPa))

Absolute gauge

error

( kPa))

%Gauge

error

13

Figure 1: Flat bottomed pontoon

Experiment 2

METACENTRIC HEIGHT OF FLOATING BODIES

INTRODUCTION:

The Stability of any vessel which is to float on water, such as a pontoon or ship, is of

paramount importance. The theory behind the ability of this vessel to remain upright must

be clearly understood at the design stage. Archimedes’ principle states that the buoyant

force has a magnitude equal to the weight of the fluid displaced by the body and is

directed vertically upward. Buoyant force is a force that results from a floating or

submerged body in a fluid which results from different pressures on the top and bottom

of the object and acts through the centroid of the displaced volume.

OBJECTIVE:

Determination of center of buoyancy

Determination of metacentric height

Investigation of stability of floating objects

APPARATUS:

Flat bottomed pontoon (Figure 1).

Hydraulic bench.

14

THEORY:

Consider a ship or pontoon floating as shown in figure 2. The center of gravity of the

body is at � and the center of buoyancy is at �. For equilibrium, the weight of the

floating body is equal to the weight of the liquid it displaces and the center of gravity

of the body and the centroid of the displaced liquid are in the same vertical line. The

centroid of the displaced liquid is called the "center of buoyancy". Let the body now

be heeled through an angle � as shown in a subsequent figure, �1 will be the position

of the center of buoyancy after heeling. A vertical line through �1 will intersect the

center line of the body at � and this point is known as the metacenter of the body

when an angle � is diminishingly small. The distance �� is known as the metacentric

height. The force due to buoyancy acts vertically up through �1 and is equal to � .

The weight of the body acts downwards through �.

Figure 2: Illustrative figure of flat bottomed pontoon

Stability of submerged objects:

Stable equilibrium: if when displaced, it returns to equilibrium position. If the

center of gravity is below the center of buoyancy, a righting moment will produced

and the body will tend to return to its equilibrium position (Stable).

Unstable equilibrium: if when displaced it returns to a new equilibrium position. If

the center of gravity is above the center of buoyancy, an overturning moment is

produced and the body is unstable.

15

Note: As the body is totally submerged, the shape of displaced fluid is not

altered when the body is tilted and so the center of buoyancy unchanged relative

to the body.

Figure 3: Stability of submerged objects

Stability of floating objects:

Metacenter point � : the point about which the body starts oscillating.

Metacentric height �� : is the distance between the center of gravity of floating body

and the metacenter.

If � lies above � a righting moment is produced, equilibrium is stable

and �� is regarded as positive.

If � lies below � an overturning moment is produced, equilibrium is unstable and �� is regarded as negative.

If � coincides with �, the body is in neutral equilibrium.

Figure 4: Stability of floating objects

16

'

Determination of Metacentric height

1- Practically

�� =� �

�� (�)

Where � = distance from pontoon centerline to added weight.

� = weight of the pontoon including �. 2- Theoretically

�� = �� + �� − ��

�� = �

�� =�

�

�� =�

�

Where: � = �� = � ∗ � ∗ �

�� =��

��

ROCEDURE:

1. Assemble the pontoon by positioning the bridge piece and mast i.e. locate

the mast in the hole provided in the base of the vessel and clamp the bridge

piece fixing screws into the locating holes in the sides of the vessel.

2. The 'plumb-bob' is attached to the mounting dowel located on the mast and

is allowed to swing clear of and below the scale provided

3. Weigh the pontoon and determine the height of its center of gravity up the

line of the mast by balancing the mast on a suitable knife edge support and

measuring the distance from knife edge to outside base of pontoon.

4. Fill the hydraulic bench measuring tank, or other suitable vessel, with water

and float the pontoon in it. Trim the balance of the pontoon by applying one

of the small weights provided to the bridge piece at the required position so

that the vessel floats without any list, this condition being indicated by the

plumb-bob resting on the zero mark.

17

5. Move the weight on the bridge piece loading pin then measure and record

the angle value with displacement.

6. Repeat the previous procedure for angle in the opposite direction i.e. apply

the weights to the opposite side of the bridge piece.

7. Calculate GM practically. Draw a relationship between θ (x-axis) and GM (y-

axis), then obtain GM when θ equals zero.

8. Calculate GM theoretically.


Pontoon length =0.35m Pontoon width b =0.20m Pontoon height h =0.075m Total weight W =1.5084kg Inclining weight P=0.3062kg

rea

din

g #

Height of center of gravity Y(m)

Depth of immersion

d(m)

Theoretical Metacentric

height GM(m)

Position of inclining weight X(m)

Angel of heel

θ (degrees)

Experimental Metacentric

height GM(m)

1

2

3

4

5

6

7

8

9

10

11

12

Important Note: Substitute θ in the law without sign (ex: θ=-13.5, tan (θ) =tan (13.5) = 0.240078759)

"في القانون بدون الاشارة θعوض الزاویة "

18


Draw a relationship between θ (x-axis) and GM (y-axis).


• Comment on the effect of changing of G on the position of metacenter

• Comment on why the values of GM at lowest level of Ɵ are likely to be less

accurate

• Explaine how unstable equilibrium might be achieved

19

Experiment 3

OSBORNE REYNOLDS DEMONSTRATION

INTRODUCTION:

The flow of real fluids can basically occur under two very different regimes namely

laminar and turbulent flow. The laminar flow is characterized by fluid particles moving in

the form of lamina sliding over each other, such that at any instant the velocity at all the

points in particular laminar is the same. The laminar near the flow boundary move at a

slower rate as compared to those near the center of the flow passage. This type of flow

occurs in viscous fluids, fluids moving at slow velocity and fluids flowing through

narrow passages.

The turbulent flow is characterized by constant agitation and intermixing of fluid

particles such that their velocity changes from point to point and even at the same point

from time to time. This type of flow occurs in low density Fluids; flow through wide

passage and in high velocity flows.

OBJECTIVE:

To perform Reynolds experiment for determination of different regimes of flow

APPARATUS:

Osborne Reynolds’ apparatus (F1-10)

Dye

Thermometer

Stopwatch

Graduated cylinder

THEORY:

Reynolds conducted an experiment for observation and determination of these regimes of

flow. By introducing a fine filament of dye in to the flow of water through the glass tube,

at its entrance he studied the different types of flow. At low velocities the dye filament

appeared as straight line through the length of the tube and parallel to its axis,

characterizing laminar flow. As the velocity is increased the dye filament becomes wavy

20

throughout indicating transition flow. On further increasing the velocity the filament

breaks up and diffuses completely in the water in the glass tube indicating the turbulent

flow.

After conducting his experiment with pipes different diameters and with water at

different temperatures Reynolds concluded that the various parameters on which the

regimes of flow depend can be grouped together in a single non dimensional parameter

called Reynolds number. Reynolds number is defined as, the ratio of inertia force per unit

volume and is given by

�� = �� / μ = �� /�

Where;

Re: Reynolds number

V: velocity of flow

D: characteristic length=diameter in case of pipe flow

ρ: mass density of fluid

µ: dynamic viscosity of fluid

ν :kinematic viscosity of fluid

Reynolds observed that in case of flow through pipe for values of Re<2000 the flow is

laminar while offer Re>40000 it is turbulent and for 2000<Re<4000 it is transition flow

PROCEDURE:

1. Obtain the Reynolds’ Apparatus and rest it on the top channel of the Hydraulics

Bench.

2. Position the outlet pipe and the overflow pipe in the well of the Hydraulics Bench.

3. Securely connect the inlet quick release connector on the Hydraulics Bench to the

inlet valve on the Reynolds’ apparatus. If the ball bearings on the quick connect

are showing the piping is not secure.

4. The feet are adjustable so that the assembly can be leveled.

5. Check that ALL the valves on the Hydraulics Bench are completely CLOSED

(clockwise).

6. CLOSE the Flow Control Valve on the Reynolds’ apparatus.

21

7. Turn the motor switch to ON.

8. OPEN the Hydraulics Bench flow control valve found on the front of the

Hydraulics bench.

9. Slowly fill the head tank to the overflow level, and then CLOSE the hydraulics

bench flow control valve.

10. Open and close the flow control valve on the Reynolds’ apparatus to admit water

to the flow visualization pipe.

11. Allow the apparatus to stand at least 10 minutes before proceeding.

12. Adjust the height of the dye reservoir assembly such that the hypodermic needle

is close to the bell mouth entrance of the visualization tube.

13. Open the inlet valve slightly until water trickles from the outlet pipe.

14. Slowly open the dye flow control valve of the dye reservoir [Note: It takes a while

for the dye to exit the hypodermic needle. Do not loosen or tighten the reservoir

screw too much, or the thread could be damaged.].

15. Once the flow regime is identified, close the dye flow control valve.

16. The flow rate can be measured using a graduated cylinder and the stopwatch.

17. The temperature can be recorded using a thermometer.

18. Other flow regimes (and flow rates) can be obtained by regulating the flow

control valve on the Reynolds’ apparatus.

19. When the experiment is finished, turn the pump motor OFF.

20. Disconnect the Reynolds’ Apparatus from the Hydraulics Bench and return it to

the storage area

22



Dose the flow condition observed occur within the expected Reynolds’s number

range for that condition?

Describe the velocity profile for laminar and turbulent flows. Dose the profile

differs between these two types of flow?

Volume collected

V(m3)

Time to collect

t(s)

Temperature (oC)

Pipe Area A(m2)

Volume flow rate Q(m3/s)

Kinematic Viscosity ʋ(m2/s)

Reynolds Number

23

Experiment 4

IMPACT OF JET (I)

INTRODUCTION:

Impact of jets apparatus enables experiments to be carried out on the reaction force

produced on vanes when a jet of water impacts on to the vane. The study of these

reaction forces is an essential step in the subject of mechanics of fluids which can be

applied to hydraulic machinery such as the Pelton wheel and the impulse turbine.

OBJECTIVE:

To investigate the reaction force produced by the impact of a jet of water on to various

target vanes (flat and semispherical)

APPARATUS:

The F1-10 Hydraulic Bench

F1-16 equipment

Stopwatch

Flat and semispherical plates.

THEORY:

When a jet of water flowing with a steady velocity strikes a solid surface (target plate),

the water is deflected to flow along the surface. Then the jet velocity can be calculated

from the measured flow rate and the nozzle exit area:

� = �

�

If the friction is neglected, also assuming that there are no losses due to shocks and the

magnitude of the water velocity remains having the same value but only its direction

changes. The pressure exerted by the water on the solid surface will everywhere be at

right angles to the surface (for a flat surface).

In the absence of friction,

Magnitude of the velocity across the surface = Incident velocity, vi

The impulse force exerted on the target = opposite to the force which acts on the

water to impart the change in direction.

24

Applying Newton’s second law in they- direction of the incident jet

�� = �� ( ��q − � )

Where

Fy = force exerted by deflector on fluid

Qm = mass flow rate and

Q� = rQ� = rA

So,

�� = r��( ��q − � )

For a static equilibrium, Fy is balanced by the applied load, W = Mg (M is the applied

mass) hence,

� = r��( ��q − � )

Graphically representing the results also will show how accurate the experimental data is.

Thus, the slope, s, of a graph of W plotted against 2 is obtained from a regression line

and this is compared to the value from:

� = r�(��q − �)

PROCEDURE:

1. Position the weight carrier on the weight platform and add weights until the top of the

target are clear of the stop and the weight platform is floating in mid position. Move

the pointer so that it is aligned with the weight platform. Record the value of weights

on the weight carrier.

2. Start the pump and establish the water flow by steadily opening the bench regulating

valve until it is fully open.

3. The vane will now be deflected by the impact of the jet. Place additional weights onto

the weight carrier until the weight platform is again floating in mid position.

4. Measure the flow rate and record the result on the test sheet, together with the

corresponding value of weight on the tray. Observe the form of the deflected jet and

note its shape.

25

5. Reduce the weight on the weight carrier in steps and maintain balance of the weight

platform by regulating the flow rate in about three steps, each time recording the

value of the flow rate and weights on the weight carrier.

6. Close the control valve and switch off the pump. Allow the apparatus to drain.

7. Replace the flat vane with semispherical vane and repeat the test


Nozzle diameter, d=0.008m Nozzle cross sectional area, A=5.0265*10-5m2 Density of Water, ρ=1000kg/m3


Plot force on vane F (N) against the velocity squared values for both flat plate and a

hemispherical cup for theoretical and experimental values on the same plot.


Comment on the agreement between your theoretical and experimental results and

give reasons for any differences

Compare between theoretical slope for flat and semispherical plate and what does

it mean?

Comment on the significant of any experimental errors

Reading No

Plate type Volume of

water collected m3

Time (sec) Mass

applied(Kg)

1

Flat plate α=90o

2

3

4

5

1

semispherical plate

α=180o

2

3

4

5

26

Experiment 5

IMPACT OF JET (II)

OBJECTIVE:

To investigate the reaction force produced by the impact of a jet of water on to various

target vanes (conical and 30o plate)

APPARATUS:


F1-16 equipment

Stopwatch

Conical and 30o plates.

PROCEDURE:

1. Position the weight carrier on the weight platform and add weights until the top of the

target are clear of the stop and the weight platform is floating in mid position. Move

the pointer so that it is aligned with the weight platform. Record the value of weights

on the weight carrier.

2. Start the pump and establish the water flow by steadily opening the bench regulating

valve until it is fully open.

3. The vane will now be deflected by the impact of the jet. Place additional weights onto

the weight carrier until the weight platform is again floating in mid position.

4. Measure the flow rate and record the result on the test sheet, together with the

corresponding value of weight on the tray. Observe the form of the deflected jet and

note its shape.

5. Reduce the weight on the weight carrier in steps and maintain balance of the weight

platform by regulating the flow rate in about three steps, each time recording the

value of the flow rate and weights on the weight carrier.

6. Close the control valve and switch off the pump. Allow the apparatus to drain.

7. Replace the 30o vane with conical vane and repeat the test

27


Nozzle diameter, d=0.008m Nozzle cross sectional area, A=5.0265*10-5m2 Density of Water, ρ=1000kg/m3


Plot force on vane F (N) against the velocity squared values for both Conical and 30o

plates for theoretical and experimental values on the same plot.


Comment on the agreement between your theoretical and experimental results and

give reasons for any differences

Comment on the significant of any experimental errors

Reading No

Plate type Volume of

water collected m3

Time (sec) Mass

applied(Kg)

1

Conical plate α=120o

2

3

4

5

1

30o plate α=30o

2

3

4

5

28

Experiment 6

ORIFICE AND FREE JET FLOW

DETERMINATION OF COEFFICIENT OF VELOCITY FROM JET

INTRODUCTION:

The orifice consists of a flat plate with a hole drilled in it. When a fluid passes through an

orifice, the discharge is often considerably less than the amount calculated on the

assumption that the energy is conserved and that the flow through the orifice is uniform

and parallel. This reduction in flow is normally due to a contraction of the stream which

takes place through the restriction and continues for some distance downstream of it,

rather than to any considerable energy loss.

With the flow through apparatus, arrangements are mad extent of the reduction in flow,

contraction of the stream and energy loss, as water discharges into the atmosphere from a

sharp-edged orifice in the base of a tank.

OBJECTIVE:

Determine Velocity coefficient for small orifice

Comparing the measured jet trajectory with the theoretically predicted jet trajectory

APPARATUS:

theF1-17 Orifice and free jet flow apparatus


Graph paper

THEORY:

From the application of Bernoulli's Equation (conservation of mechanical energy for a

steady, incompressible, frictionless flow): the ideal orifice outflow velocity at the jet vena

contracta (narrowest diameter) is where h is the height of fluid above the orifice.

�� = ��

29

Where h is the height of fluid above the orifice.

The actual velocity is

� = �� < 1 … … … … … … ..(�)

Cv is the coefficient of velocity, which allows for the effects of viscosity a

Cv can be determined from the trajectory of the jet using the following argument:

Neglecting the effect of air resistance, the horizontal component of the jet velocity can

be assumed to remain constant so that in time, t, the horizontal distance travelled,

� = �� … … … … … … ..(�)

Because of the action of gravity, the fluid also acquires a downward vertical (y-direction)

component of velocity. Hence, after the same time, t, (i.e. after travelling a distance x) the

jet will have a y displacement given by

� = ��

�

This can be rearranged to give:

� = ��

�… … … … … … ..(�)

Substitution for t from (3) into (2) and for v from (1) into (2) yields the result:

�� =�

��

Hence, for steady flow conditions, i.e. Constant h, Cv can be determined from the x, y

co-ordinates of the jet. A graph of x plotted against �yh will have a slope of 2Cv

30

PROCEDURE:

For this experiment, you will need the Orifice and Free Jet Flow module and graph paper.

Figure 1: Orifice and Free Jet Flow Module

1. Position the overflow tube to give a high head. Note the value of the head.

2. The jet trajectory is obtained by using the needles mounted on the vertical

backboard to

follow the profile of the jet.

3. Release the securing screw for each needle in turn and move the needle until its

point is just immediately above the jet and re-tighten the screw.

4. Attach a sheet of paper to the back-board between the needle and board and

secure it in place with the clamp provided so that its upper edge is horizontal.

5. Mark the location of the top of each needle on the paper. Note the horizontal

distance from the plane of the orifice (taken as x = 0) to the co-ordinate point

marking the position of the first needle.

6. This first co-ordinate point should be close enough to the orifice to treat it as

having the value y = 0.

7. Thus y displacements are measured relative to this position.

8. Estimate the likely experimental errors in each of the quantities measured.

9. Repeat this test for a low reservoir head.

10. Repeat this test for a low reservoir head.

11. Then repeat the above procedure for the second orifice.

Figure 2: Orifice and Jet Apparatus

31


Small Orifice: Diameter=3mm=0.003m

Orifice Diameter

d(m)

Head h(m)

Horizontal Distance

X(m)

Vertical Distance

y(m)

√(��) (m)

1 0.003 0.0135 2 0.003 0.0635

3 0.003 0.1135 4 0.003 0.1635 5 0.003 0.2135 6 0.003 0.2635 7 0.003 0.3135 8 0.003 0.3635

Large Orifice: Diameter=6mm=0.006m

Orifice

Diameter d(m)

Head h(m)

Horizontal Distance

X(m)

Vertical Distance

y(m)

√(��) (m)

1 0.006 0.0135 2 0.006 0.0635

3 0.006 0.1135 4 0.006 0.1635 5 0.006 0.2135 6 0.006 0.2635 7 0.006 0.3135 8 0.006 0.3635


Plot x against �yh and determine the slope of the graph.

The velocity coefficient Cv is equal to the average slope/2.


Compare the values of Cv with values reported in the textbook for an Orifice Meter and

discuss any difference (or look for web resources).

32

Experiment 7

ORIFICE AND FREE JET FLOW

DETERMINATION OF COEFFICIENT OF DISCHARGE FROM JET

OBJECTIVE:

• To determine Discharge coefficient of small orifice for constant head flow

APPARATUS:

theF1-17 Orifice and free jet flow apparatus


Stop watch

Graduated cylinder

THEORY:

The ideal (theoretical) orifice outflow velocity at the jet vena contracta (narrowest

diameter) is:

�� = ��

Where h is the height of fluid above the orifice.

33

The actual velocity is:

� = ��

Cv is the coefficient of velocity, which allows for the effects of viscosity

The actual flow rate of the jet is defined as:

�� = ��

Where: Ac is the cross-sectional area of the vena contracta, given by: �� = ��

Ao is the orifice area and Cc is the coefficient of contraction and, therefore, Cc <1

Hence;

�� = ��

The product CcCv is called the discharge coefficient, Cd , so finally

�� = ��

If Cd is assumed to be constant, then a graph of Qact plotted against will be linear and the

slope,

� = ��

PROCEDURE:

1. Position the reservoir across the channel on the top of the hydraulic bench and

level the reservoir by the adjustable feet using a spirit level on the base.

2. Remove the orifice plate by releasing the two knurled nuts and check the orifice

diameter; take care not to lose the O-ring seal.

3. Replace the orifice and connect the reservoir inflow tube to the bench flow

connector.

4. Position the overflow connecting tube so that it will discharge into the volumetric

tank; make sure that this tube will not interfere with the trajectory of the jet

flowing from the orifice.

5. Turn on the pump and open the bench valve gradually. As the water level rises in

the reservoir towards the top of the overflow tube, adjust the bench valve to give a

water level of 2 to 3mm above the overflow level. This will ensure a constant

head and produce a steady flow through the orifice.

6. Measure the flow rate by timed collection using the measuring cylinder provided

and note that the reservoir head value.

34

7. Repeat this procedure for different heads by adjusting the level of the overflow

tube. The procedure should also be repeated for the second orifice


Small Orifice: Diameter=3mm=0.003m

Orifice

Diameter d(m)

Head h(m)

Volume V(m3)

Time t(sec)

Actual flow rate Qt(m

3/S)

√� (m)0.5

1 0.003 2 0.003

3 0.003

4 0.003

5 0.003

Large Orifice: Diameter=6mm=0.006m

Orifice

Diameter d(m)

Head h(m)

Volume V(m3)

Time t(sec)

Actual flow rate Qt(m

3/S)

√� (m)0.5

1 0.006 2 0.006

3 0.006

4 0.006

5 0.006


Plot flow rate Qt vs. √h and determine the slope of the graph.

The coefficient of discharge Cd can then be calculated from the slope equation


Compare the values of Cd with values reported in the textbook for an Orifice

Meter and discuss any difference (or look for web resources).

Find the value of Cc for both orifices.

35

Experiment 8

COEFFICIENT OF DISCHARGE FOR A RECTANGULAR NOTCH

INTRODUCTION:

Discuss why there is a discrepancy between the theoretical and computed

discharge values

What are the limitations of the experiment?

How does the Cd value computed from the slope?

The reliability of weir measurements is affected by construction and installation, but

when properly constructed and installed, weirs are one of the simplest and most accurate

methods of measuring water flow. In fact, hydrologists and engineers treat this as a

simple method of measuring the rate of fluid flow in small to medium-sized streams, or in

industrial discharge locations.

There are different types of weir. It may be a simple metal plate with a V-notch cut into

it, or it may be a concrete and steel structure across the bed of a river. Common weir

constructions are the rectangular weir and the triangular or v-notch weir.

OBJECTIVE:

To determine the 'Coefficient of Discharge' for a rectangular weir.

APPARATUS:

The F1-10 Hydraulics Bench

The F1-13 Stilling baffle

The F1-13 Rectangular

Vernier Height Gauge

Stop Watch

Spirit Level

THEORY:

36

The objective of this experiment is to study the relation between the discharge coefficient

and the parameters influencing the flow. Rectangular shape opening weir is used in this

experiment. Stilling baffle is used to ensure minimum turbulence. It will act as a reservoir

to collect water volume and slowly disperse in the water from the opening at the bottom

of the stilling baffle.

Rectangular Weir is used in practiced to measure a small free flow. A rectangular notch

is a thin square edged weir plate installed in a weir channel as shown in figure below. The

rectangular weir is able to measure higher flows than the v-notch weir and over a wider

operating range.

Figure 1: Rectangular Notch

Consider the flow in an element of height �ℎ at a depth h below the surface. Assuming

that the flow is everywhere normal to the plane of the weir and that the free surface

remains horizontal up to the plane of the weir, then velocity through element �2�ℎ

∴ Theoretical discharge through element

�� = �.�� = ��.�.��

Integrating between h = 0 and h = H,

Total theoretical discharge

37

�� = � ��.�.��

�

= �� .��

�

�

So,

�� =�

��

��

Where, Cd = Coefficient discharge

B = Width of notch

H = Head above bottom of notch

Q = Flow rate

In practice the flow through the notch will not be parallel and therefore will not be

normal to the plane of the weir. The free surface is not horizontal and viscosity and

surface tension will have an effect. There will be a considerable change in the shape of

the nappe as it passes through the notch with curvature of the stream lines in both vertical

and horizontal planes in particular the width of the nappe is reduced by the contractions

at each end.

�� = �� = ��

� � �� /�

PROCEDURE:

1. Weir apparatus was leveled on the hydraulic bench and the rectangular notch weir

was installed.

2. Hydraulic bench flow control valve was opened slowly to admit water to the

channel until the water discharges over the weir plate. The water level was

ensured even with the crest of the weir.

3. The flow control valve was closed and the water level was allowed to stabilize.

4. Vernier Gauge was set to a datum reading using the top of the hook. The gauge

was positioned about half way between the notch plate and stilling baffle.

5. Then, water was admitted to the channel. The water flow was adjusted by using

the hydraulic bench flow control valve to obtain heads (H).

6. Water flow condition was left to stabilize, head readings were taken in every

38

increasing of 1 cm.

7. Step 4 and 5 were repeated for different flow rate.

8. The readings of volume and time using the volumetric tank were taken to

determine the flow rate. The volume taken was constant which 3L.

9. The results were recorded in the tables.


V(L) H (m) Time (s) Average

Time (s) Q (m3/s)

T1 T2 T3


Plot Qact against H 3/2 and determine the slope of the graph. Then the coefficient of

discharge Cd can then be calculated.



discharge values



Experiment 9

39

COEFFICIENT OF DISCHARGE FOR A TRIANGULAR NOTCH

OBJECTIVE:

To determine the 'Coefficient of Discharge' for a triangular or v-notch weir.

APPARATUS:

The F1-10 Hydraulics Bench

The F1-13 Stilling baffle

The F1-13 Triangular or v-notch weir

Vernier Height Gauge

Stop Watch

Spirit Level

THEORY:

The v-notch weir is a notch with a V shape opening. V-notch weir typically used to

measure low flows within a narrow operating range. The angle of the v-notch in the

figure 1 above is 90°.

�� =�

��

�

��

��

�� = �� =�

��

�

��

��

Where, Cd = Coefficient discharge

� = The angle of notch

H = Head above bottom of notch

Q = Flow rate

PROCEDURE:

Figure 1: V-notch weir

40

1. Weir apparatus was leveled on the hydraulic bench and the V- notch weir was

installed.

2. Hydraulic bench flow control valve was opened slowly to admit water to the

channel until the water discharges over the weir plate. The water level was

ensured even with the crest of the weir.

3. The flow control valve was closed and the water level was allowed to stabilize.

4. Vernier Gauge was set to a datum reading using the top of the hook. The gauge

was positioned about half way between the notch plate and stilling baffle.

5. Then, water was admitted to the channel. The water flow was adjusted by using

the hydraulic bench flow control valve to obtain heads (H).

6. Water flow condition was left to stabilize, head readings were taken in every

increasing of 1 cm.

7. Step 4 and 5 were repeated for different flow rate.

8. The readings of volume and time using the volumetric tank were taken to

determine the flow rate. The volume taken was constant which 3L.

9. The results were recorded in the tables.


V(L) H (m) Time (s) Average

Time (s) Q (m3/s)

T1 T2 T3


Plot Qact against H 5/2 and determine the slope of the graph. Then the coefficient of

discharge Cd can then be calculated.



41

discharge values



Compare between Cd value of both rectangular and triangular notches.

Experiment 10

HYDRAULIC GRADIENT WITH GROUND WATER FLOW

42

INTRODUCTION:

Ground water flows from areas of high hydraulic head (high water-level elevation) to

areas of low head (low water level elevation). The hydraulic gradient is the rate of change

in the total hydraulic head per unit distance of flow in a given direction.

The hydraulic gradient is usually estimated using groundwater elevation measurements

from observation wells and peizometer .Estimates of the direction and magnitude of the

hydraulic gradient in a given part of the aquifer may then be used with estimates of the

hydraulic conductivity and the effective porosity to characterize the direction and rate of

groundwater flow (i.e., groundwater seepage velocity) using a form of Darcy’s Law.

OBJECTIVE:

To demonstrate ground flow and the resulting between two different potentials

APPARATUS:

S-11 Ground Flow/Well Abstraction Unit

0.1m3 of washed well graded coarse sand, range 0.6-2.0mm

Stopwatch

Volumetric measuring cylinder

THEORY:

The linear relationship between head loss h and flow rate Q expressed as approach

velocity V is given by Darcy’s Law

V = kdh

dL

Where

V=Volumetric flow rate per unit cross-sectional area

��

��=Hydraulic gradient

K=Permeability coefficient

V may also be calculated from the flow rate using the average wetted area of sand (as

calculated from the water levels)

43

� =�

�

PROCEDURE:

1. Turn on the water supply

2. Open the left hand flow control valve fully

3. Adjust the right hand flow control valve until a steady head is maintained .this will be

indicated by manometer tube No 13

4. Allow conditions to stabilize for several minutes

5. Record the manometer levels

6. Perform a timed volume collection to measure flow rate (Q) out of drainage tube


Volume Collected =----------------------

Time to Collect = -------------------------

Permeability coefficient (K) =-----------------------

Man

om

eter

tub

e

1 2 3 4 5 6 7 8 9 10

11

12

13

14

15

16

17

18

19

Hei

ght

( h

)

mm

Dis

tan

ce (

L )

mm


44

Draw a graph of water height (h) against peizometer (tapping) distance (L) from

well


How the hydraulic gradient did obtain from graph Compare to the hydraulic

gradient calculated using the measured flow rate?

Give reasons to any discrepancies; suggest changes to the experimental method

that might help to reduce such discrepancies

Comment on the effect of k on the gradient

References:

45

Alastal .K and Mousa.M (2015) .Fluid Mechanics and Hydraulics Lab Manual

EPA. (2014). A Tool for Estimating Groundwater Flow Vectors

Fuqha.M. (2013). Thermal Fluid Laboratory manual

NSCET. (2013). Hydraulic Engineering laboratory

Syahiirah.N (2015). CHE241 - Lab Report -Flow over Weirs, https://www.academia.edu/

18747051/CHE24 _Lab_Report_Solteq_Flow_Over_Weirs_FM26_2015_

The Department of Civil and Architectural Engineering-Qatar University-Lab manual of

fluid mechanics

HYDRAULIC LABORATORY MANUAL

Documents

Transcript of HYDRAULIC LABORATORY MANUAL