Lab Manual (Hydraulics Engineering)

HYDRAULICS ENGINEERING LAB MANUAL

1 2008-CIVIL-87

TABLE OF CONTENTS

Experiment # 01 …………………………………………………………………….2

TO DETERMINE MANNING’S ROUGHNESS COEFFICIENT “n” AND CHEZY’S CO-EFFICIENT “C”

IN A LABORTARY FLUME

Experiment # 02 ……………………………………………………………………11

TO INVESTIGATE THE RELATIONSHIP BETWEEN SPECIFIC ENERGY (SE) AND DEPTH OF FLOW(Y) IN A LABORATORY FLUM

Experiment # 03 ……………………………………………………………..........16

To study the flow characteristics over the hump or weir in a rectangular channel

Experiment # 04 …………………………………………………………………...25

TO STUDY THE FLOW CHARACTERISTICS OF HYDRAULIC JUMP DEVELOPED IN LAB FLUME


2 2008-CIVIL-87

EXPERIMENT NO. 1

TO DETERMINE MANNING’S ROUGHNESS COEFFICIENT “n” AND

CHEZY’S CO-EFFICIENT “C” IN A LABORTARY FLUME.

OBJECTIVE:

To study the variation in “n” with respect to discharge.

To study changes in “c” with respect to discharge.

To manipulate/investigate relation b/w: n” and “c”.

To learn the procedure of determining “n” and “c” of any existing channel.

APPARATUS:

S6 glass sided Tilting lab flume with manometric flow arrangement and slope adjusting scale.

Point gauge (For measuring depth of channel)

RELATED THEORY:

FLUME

Open channel generally supported on or above the ground.

UNIFORM FLOW:

A uniform flow is one in which flow parameters and channel parameters remain same with respect to

distance b/w two sections.

NON-UNIFORM FLOW:

A non-uniform flow is one in which flow parameters and channel parameters not remain same with

respect to distance b/w two sections.

STEADY FLOW: A steady flow is one in which the conditions (velocity, pressure and cross-section) may differ from point to point but DO NOT change with time.

UNSTEADY FLOW:

If at any point in the fluid, the conditions change with time, the flow is described as unsteady. (In practice there are always slight variations in velocity and pressure, but if the average values are constant, the flow is considered steady.

STEADY UNIFORMM FLOW:

Conditions do not change with position in the stream or with time. An example is the flow of water in a pipe of constant diameter at constant velocity.

STEADY NON-UNIFORMM FLOW:

Conditions change from point to point in the stream but do not change with time. An example is flow in a tapering pipe with constant velocity at the inlet - velocity will change as you move along the length of the pipe toward the exit.


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STEADY UNIFORMM FLOW:

At a given instant in time the conditions at every point are the same, but will change with time. An example is a pipe of constant diameter connected to a pump pumping at a constant rate which is then switched off.

UNSTEADY NON-UNIFORMM FLOW:

Every condition of the flow may change from point to point and with time at every point. For example

waves in a channel.

MANNINGS ROUGNESS FORMULA

The Manning formula states:

Where:

V is the cross-sectional average velocity (L/T; ft/s, m/s)

k is a conversion factor of 1.486 (ft/m)1/3 for U.S. customary units and 1 in SI Units.

n is the Manning coefficient (T/L1/3; s/m1/3)

Rh is the hydraulic radius (L; ft, m)

S is the slope of the water surface or the linear hydraulic head loss (L/L) (S = hf/L)

Manning formula is used to estimate flow in open channel situations where it is not practical to construct a weir or flume to measure flow with greater accuracy. The friction coefficients across weirs and orifices are less subjective than n along a natural (earthen, stone or vegetated) channel reach. Cross sectional area, as well as n', will likely vary along a natural channel. Accordingly, more error is expected in predicting flow by assuming a Manning's n, than by measuring flow across a constructed weirs, flumes or orifices.

HYDRAULICS RADIUS:

The hydraulic radius is a measure of channel flow efficiency.

Where:

Rh is the hydraulic radius,

A is the cross sectional area of flow ,

P is wetted perimeter .

The greater the hydraulic radius, the greater the efficiency of the channel and the less likely the river is to flood. For channels of a given width, the hydraulic radius is greater for the deeper channels.

The hydraulic radius is not half the hydraulic diameter as the name may suggest. It is a function of the shape of the pipe, channel, or river in which the water is flowing. In wide rectangular channels, the

http://en.wikipedia.org/wiki/Length

http://en.wikipedia.org/wiki/Time

http://en.wikipedia.org/wiki/U.S._customary_units

http://en.wikipedia.org/wiki/Hydraulic_head

http://en.wikipedia.org/wiki/Weir

http://en.wikipedia.org/wiki/Flume

http://en.wikipedia.org/wiki/Orifice

http://en.wikipedia.org/wiki/Wetted_perimeter

http://en.wikipedia.org/wiki/Hydraulic_diameter


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hydraulic radius is approximated by the flow depth. The measure of a channel's efficiency (its ability to move water and sediment) is used by water engineers to assess the channel's capacity.

CHEZY’S FORMULA:

Chezy formula can be used to calculate mean flow velocity in conduits and is expressed as

v = c (R S) 1/2

Where v = mean velocity (m/s, ft/s) c = the Chezy roughness and conduit coefficient R = hydraulic radius of the conduit (m, ft) S = slope of the conduit (m/m, ft/ft)

PROCEDURE:

Measure Channel (Flume) width.

Adjust the suitable slope.

Fill the S-6 tilting flume up to some depth.

Note down the readings of differential manometer and see the corresponding discharge from

the discharge chart.

Note down the depth of flow at different points. (e.g. 2m,4m,6m)

Calculate the Co-efficient “C” and “n” accordingly by the given formulas.

PRECAUTIONS:

Take manometric reading only when flow is steady.

The height should not be measured near the joints or at points where there is turbulence in

flume.

The height measuring needle must be adjusted precisely.

The tip of the needle must be just touching the water surface while taking observations.

http://en.wikipedia.org/wiki/Sediment

http://www.engineeringtoolbox.com/hydraulic-equivalent-diameter-d_458.html


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Determination of Slope of Energy Line:

0

0.02

0.04

0.06

0.08

0.1

0.12

0.14

0.16

0.18

0.2

0 1 2 3 4 5 6 7

De

pth

of

Ene

rgyL

ine

(m

)

Distance (m)

For Q= 0.00894 m³/s For Q= 0.00894 m³/s

0

0.02

0.04

0.06

0.08

0.1

0.12

0.14

0.16

0.18

0.2

0 1 2 3 4 5 6 7

De

pth

of

Ene

rgyL

ine

(m

)

Distance (m)

For Q= 0. 01200m³/s


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0

0.02

0.04

0.06

0.08

0.1

0.12

0.14

0.16

0.18

0.2

0 1 2 3 4 5 6 7

De

pth

of

Ene

rgyL

ine

(m

)

Distance (m)

For Q= 0.01600 m³/s

0

0.02

0.04

0.06

0.08

0.1

0.12

0.14

0.16

0.18

0.2

0 1 2 3 4 5 6 7

De

pth

of

Ene

rgyL

ine

(m

)

Distance (m)

For Q= 0.01833 m³/s


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0

0.02

0.04

0.06

0.08

0.1

0.12

0.14

0.16

0.18

0.2

0 1 2 3 4 5 6 7

De

pth

of

Ene

rgyL

ine

(m

)

Distance (m)

For Q= 0.01918 m³/s

0

0.02

0.04

0.06

0.08

0.1

0.12

0.14

0.16

0.18

0.2

0 1 2 3 4 5 6 7

De

pth

of

Ene

rgyL

ine

(m

)

Distance (m)

For Q= 0.020390 m³/s


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Determination of Manning’s and Chezy’s Coefficient:

Sr. No

Bed Slope

So

Q (m³/sec)

y= Depth Of Flow (mm)

Area Of flow

A=(b x

y) m²

Wetted Perimeter P= b + 2y

(m)

Hydraulic Radius R=A/P

(m)

Flow Velocity V= Q/A (m/sec)

Slope Of Energy

Line S

Manning's Roughness Coefficient

Chezy's Coefficient

y1 y2 y3 yavg n1 n2 C1 C2

1 0.002 0.00894 55 59 60 58.000 0.0174 0.416 0.0418 0.514 0.0006523 0.0104 0.0059 56.188 98.389

2 0.002 0.012 72 73 60 68.333 0.0205 0.437 0.0469 0.585 0.0012705 0.0098 0.0078 60.395 75.777

3 0.002 0.016 79 81 79 79.667 0.0239 0.459 0.0520 0.669 0.0005000 0.0092 0.0046 65.609 131.218

4 0.002 0.01833 84 83 81 82.667 0.0248 0.465 0.0533 0.739 0.0002416 0.0085 0.0029 71.574 205.934

5 0.002 0.01918 84 87 85 85.333 0.0256 0.471 0.0544 0.749 0.0002500 0.0085 0.0030 71.827 203.156

6 0.002 0.02039 92 92 85 89.667 0.0269 0.479 0.0561 0.758 0.0005573 0.0086 0.0045 71.551 135.546

Graph b/w Discharge and Chezy’s Coefficient;

0

0.005

0.01

0.015

0.02

0.025

40.000 45.000 50.000 55.000 60.000 65.000 70.000 75.000

Q (

m³/

s)

Chezys Coefficient


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Graph b/w Discharge and Manning’s Coefficient;

Graph b/w Chazy’s Coefficient and Manning’s Coefficient;

0

0.005

0.01

0.015

0.02

0.025

0.0060 0.0065 0.0070 0.0075 0.0080 0.0085 0.0090 0.0095 0.0100 0.0105 0.0110

Q (

m³/

s)

Manning's Coefficient (n)

0.0000

0.0020

0.0040

0.0060

0.0080

0.0100

0.0120

50.000 55.000 60.000 65.000 70.000 75.000

Man

nin

g's

Co

eff

icie

nt

(n)

Chezy Coefficient,C


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RESULTS:

Value of Chezy’s Co-efficient increases with increase in discharge.

Manning’s Co-efficient decreases with increase in discharge.

There is Inverse Relation b/w Manning’s Co-efficient and Chezy’s Co-efficient.


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EXPERIMENT#02

TO INVESTIGATE THE RELATIONSHIP BETWEEN SPECIFIC

ENERGY (SE) AND DEPTH OF FLOW(Y) IN A LABORATORY FLUME

OBJECTIVES:

i) To study the variations in specific energy as a function of depth of flow for a given discharge

in a lab flume.

ii) To validate the theories of E-Y diagram( S.E and Depth) diagrams

APPARATUS:

Tilting lab flume with manometric flow arrangement and slope adjusting scale.

Hook gauge

RELATED THEROY:

FLUME:

It is a channel supported above the ground level.

SPECIFIC ENERGY:

S.E if the total energy per unit weight measured relative to the channel’s bed and mathematically,

Where E = S.E of the per unit weight

Y= depth of flow

V2/2g = kinetic head or velocity head


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When slopes are involves,

For mild slopes,

SPECIFIC ENERGY CURVE:

It is the plot which shows the variations in S.E as a function of Depth of flow.

CRITICAL DEPTH:

It is the depth of flow in the channel at which specific energy is minimum. Mathematically

FROUD’s NUMBER:

It is the ratio of inertial forces to the gravitational forces. Mathematically it is:


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CRITICAL FLOW:

It is the flow corresponding to the critical depth with Froud’s Number = 1

CRITICAL VELOCITY:

Velocity corresponding to critical depth .

SUB-CRITICAL FLOW:

It is the flow with larger depths and less flow velocities or flow at which Froud’s Number is les than 1 .

SUPER CRITICAL FLOW:

It is the flow corresponding to the lesser depths and larger flow velocities. And flow will be called as

super critical flow for Froud’s Number

ALTERNATE DEPTHS:

For the value of the specific energy other than at the critical point for a constant discharge, there are

two water depths.

i) One is greater than critical depths

ii) Other is Less than critical depths

These two depths for a given specific energy are termed as alternate Depths .


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PROCEDURE:

1. Maintain the constant discharge in open channel

2. For one particular value of flow, find out the water depths at the different locations and

calculate the average depth of flow.

3. Calculate the specific energy using this relation:

4. Repeat this by varying the value of slopes.

5. Draw E –y curves

6. Find out the critical depths and E min

7.

PRECAUTIONS:



flume.




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OBSERVATION &CALCULATION:

WIDTH OF FLUME = 0.3 m

Sr# SLOPE Discharge

(m³/s)

DEPTH OF FLOW (m) Velocity (m/s)

V²/2g (m)

SPECIFIC ENERGY

Y1 Y2 Y3 Yavg

1 0 0.012646 0.0814 0.078 0.0725 0.0773 0.5453 0.0278 0.1051

2 1 : 40 0.012646 0.031 0.026 0.027 0.0280 1.5055 0.0767 0.1047

3 1 : 60 0.012646 0.037 0.031 0.033 0.0337 1.2521 0.0638 0.0975

4 1 : 100 0.012646 0.041 0.037 0.035 0.0377 1.1191 0.0570 0.0947

5 1 : 200 0.012646 0.059 0.043 0.047 0.0497 0.8487 0.0433 0.0929

6 1 : 500 0.012646 0.064 0.0669 0.0647 0.0652 0.6465 0.0330 0.0982

E~Y DIAGRAM (Specific Energy Curve):

RESULTS:

Yc= 0.048 m

Emin= 0.092m

Flow below 0.048 m is super critical.

Flow above 0.048 m is sub critical.

0

0.01

0.02

0.03

0.04

0.05

0.06

0.07

0.08

0.09

0 0.02 0.04 0.06 0.08 0.1 0.12 0.14

De

pth

,Y (

m)

Specific Energy,E (m)

SUB CRITICAL FLOW

SUPER CRITICAL FLOW

E=Y CurveE~Y

YC VC² /2g

Emin


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EXPERIMENT # 03

TO STUDY THE FLOW CHARACTERISTICS OVER THE HUMP OR

WEIR IN A RECTANGULAR CHANNEL

OBJECTIVE

To study the variation of flow with the introduction of different types of weirs in the flume.

APPARATUS

S6 tilting flume apparatus which consists of

Orifice

Differential manometer

Large chamber to study flow

Controlling meter to vary slope.

Hook gauge/point gauge to measure the depth

Broad crested weirs

Rounded corner weir

Sharp corner weir

RELATED THEORY

HUMP

Stream lined construction over the bed of a channel is called hump. OR The raised bed of the channel at a certain location is called as hump. WEIR

It is the streamlined wall or structure constructed across a river or a stream at a suitable location. It is commonly used to raise the water level at a river or stream to divert the required amount of water into an off taking canal. Weirs can be gated or ungated. Gated weir is called as BARRAGE

FLOW OVER WEIR OR HUMP

a) SUB CRITICAL FLOW

Consider a horizontal, frictionless rectangular channel of width B carrying a discharge Q at depth y1.

Let the flow be subcritical. At section 2, a smooth hump of height ΔZ is built on the floor. Since there are

no energy losses between sections 1 and 2, construction of a hump causes the specific energy at section

to decrease by ΔZ. Thus the specific energies at sections 1 and 2 are,


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E2 = E1 - ∆Z

Channel transition with a hump

Since the flow is subcritical, the water surface will drop due to a decrease in the specific energy.

In above Fig the water surface which was at P at section 1 will come down to point R at section 2. The

depth y2 will be give by,

b) SUPERCRITICAL FLOW

If Y1 is in the supercritical flow regime, Fig below shows that the depth of flow increases due to the

reduction of specific energy. Point P` corresponds to y1 and point R` to depth at the section 2. Up to the

critical depth, y2 increases to reach yc at ΔZ = ΔZmax. For ΔZ > ΔZmax , the depth over the hump y2 = yc will

remain constant and the upstream depth y1 will change. It will decrease to have a higher specific energy

E1`by increasing velocity V1.

Specific energy diagram


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EFFECT OF HUMP HEIGHT ON THE DEPTH OF FLOW:

Height of hump is less than critical hump height then there will be sub critical flow over the hump, downstream of the hump and upstream of the hump. Depth of flow over the hump will decrease by a certain amount as there is a slight depression in the water. Further increase in the height of hump will create more depression of water surface over the hump until finally the depth becomes equals to the critical depth. When the hump height will be equal to the critical depth then there will be critical flow over the hump, sub critical on the upstream side and super critical just downstream of the hump. If the hump is made still higher, critical depth will maintain over the hump and depth on upstream side will be increased. This phenomenon is referred to as damming action. Critical Hump Height is the minimum hump height that can cause the critical depth over the hump is called as critical hump height.

CASE 1 When Z < << Zc and y2 >>> yc

The flow conditions will be sub critical

Upstream level increases

Over hump y2 > yc

At downstream depth is recovered after a long distance

CASE 2 When Z = Zc

Upstream level increases

Over hump y2 = yc


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CASE 3 When Z > Zc

Afflux on upstream side (damming action)

y1 > y3 and y2 = yc

At this stage E1 = y1 + v12/2g + afflux

DAMMING ACTION: It is the sudden increase of the water depth at upstream side due to increase in hump height.

PROCEDURE:

1. Fix the slope of the flume 2. Introduce a round corner wide crested weir in the flume at certain location 3. Set the discharge in the flume having certain value. 4. Note depth of flow at upstream side of hump, over the hump and downstream side of hump at

certain point. 5. Repeat steps 2-4 for the other discharges 6. Repeat the same procedure for sharp cornered wide crest weir 7. Predict the type of flow at every section 8. Compare depths with critical depth for every discharge value and report the type of flow. 9. Draw flow profile over the hump for both types of humps.

PRECAUTIONS:


The height should not be measured near the joints or at points where there is turbulence in flume.




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OBSERVATION & CALCULATION:

WEIR TYPE Height

(mm) Width (mm)

ROUND CORNER 120 400

SHARP CORNER 60 400

Sr.# WEIR TYPE

Q m3/sec

Yc (mm)

DEPTH OF FLOW (mm) FLOW CONDITOINS

Up Stream over hump Down Stream

Y1 Y2 Y3 Yavg Y1 Y2 Y3 Yavg Y1 Y2 Y3 Yavg u/s Over hump

d/s

1

ROUND CORNER

WEIR

0.006323 35.64 172 172 171 171.67 162 150 140 150.67 11 19 24 18.00 Sub Critical Sub

Critical Super

Critical

2 0.01058 50.24 189 190 188 189.00 177 161 142 160.00 12 22 32.5 22.17 Sub Critical Sub

Critical Super

Critical

3 0.013263 58.41 202 202 200 201.33 190 169 152 170.33 23 25 37 28.33 Sub Critical Sub

Critical Super

Critical

4

SHARP CORNER

WEIR

0.008488 43.37 120 121 120 120.33 115 97 92 101.33 19 23 23 21.67 Sub Critical Sub

Critical Super

Critical

5 0.011659 53.60 134 135 133 134.00 127 100 99 108.67 20 30 39 29.67 Sub Critical Sub

Critical Super

Critical

6 0.015228 64.04 148 149 148 148.33 140 108 106 118.00 30 37 44 37.00 Sub Critical Sub

Critical Super

Critical


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SURFACE WATER PROFILES:

Round Corner Broad Crested Weir:

0

0.05

0.1

0.15

0.2

0.25

0 1 2 3 4 5 6 7 8

WA

TER

DEP

TH (

m)

HORIZONTAL DISTANCE (m)

Q = .006323 m3/s

0

0.05

0.1

0.15

0.2

0.25

0 1 2 3 4 5 6 7 8

WA

TER

DEP

TH (

m)


Q = .01053m3/s


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Sharp Corner Broad Crested Weir:

0

0.05

0.1

0.15

0.2

0.25

0 1 2 3 4 5 6 7 8

WA

TER

DEP

TH (

m)


Q = .0.013263m3/s

0

0.02

0.04

0.06

0.08

0.1

0.12

0.14

0 1 2 3 4 5 6 7 8

WA

TER

DEP

TH (

m)


Q = 0.008488m3/s


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0

0.02

0.04

0.06

0.08

0.1

0.12

0.14

0 1 2 3 4 5 6 7 8

WA

TER

DEP

TH (

m)


Q = 0.011659m3/s

0

0.02

0.04

0.06

0.08

0.1

0.12

0.14

0.16

0.18

0 1 2 3 4 5 6 7 8

WA

TER

DEP

TH (

m)


Q = 0.015228 m3/s


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RESULTS:

The Flow is sub Critical at upstream in both cases.

The Flow is subcritical over weir in both cases.

The Flow in all of the above cases is Supercritical at the downstream side immediately after the weir.


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EEXXPPEERRIIMMEENNTT ## 0044

TO STUDY THE FLOW CHARACTERISTICS OF HYDRAULIC JUMP

DEVELOPED IN LAB FLUME

OBJECTIVES

1. To physically achieve the hydraulic jump in lab flume.

2. To measure the physical dimensions of hydraulic jump.

3. To calculate the energy loses through hydraulic jump.

4. To plot water surface profiles of the hydraulic jump for various discharges.

APPARATUS

S-6 tilting lab flume with

Manometer

Flow arrangement

Slope adjusting scale

Hook gauge

RELATED THEORY

HYDRAULIC JUMP

The rise of water level which takes place due to transformation of super critical flow to sub critical flow

is termed as hydraulic jump.

PRACTICAL APPLICATIONS OF HYDRAULIC JUMP

To dissipate the energy of water flowing over the hydraulic structures and thus preventing scouring (vertical erosion) downstream of structures.

To recover head or raise the water level on the downstream of a hydraulic structure and thus to maintain high water level in the channel for irrigation or other water distribution purposes.

To increase the weight of apron and thus reduce uplift pressure under the structure by raising water depth on the apron. Apron: Layer of flexible material provided on the downstream floor. It act as an inverted filter.


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To mix chemicals used for water filtration etc.

EXPRESSION FOR DEPTH OF HYDRAULIC JUMP

From the figure below. Depth of hydraulic jump =

We can find d2 , for known value of d1 , by using expression,

EXPRESSION FOR LOSS OF ENERGY DUE TO HYDRAULIC JUMP

On simplifying, we can find head loss for known values of d1 and d2 ,

LENGTH OF HYDRAULIC JUMP

The length between two sections where one section is taken just before the hydraulic jump and second

section is taken just after the hydraulic jump is termed as length of hydraulic jump.

Approximate length of hydraulic jump = 5 -7 times depth of hydraulic jump


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LOCATIONOF HYDRAULIC JUMP

Location of hydraulic jump is governed by two factors,

I) d2 (Depth of flow just after the hydraulic jump)

II) Y2 (Normal depth of flow on downstream side of hydraulic structure)

CASE – 01 When d2 < Y2

In Case – 01, Hydraulic jump will be formed over the glaces of hydraulic structure as shown in the figure

and it will be weak jump/Submerged jump.

CASE – 02 When d2 = Y2

In Case – 02, Hydraulic jump will be formed on the toe of hydraulic structure as shown in the figure and

it will be a relatively strong jump than Case - 01.

U/S D/S

y2

Crest

d2

U/S D/S y2

Crest


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CASE – 03 When d2 > Y2

In Case – 03, Hydraulic jump will be formed ahead of hydraulic structure as shown in the fig. And it will

be a relatively strong jump as compared to Case – 01 and Case – 02.

Comparatively, Case – 02 is ideal case with sufficient energy dissipation and structure will also be safe

(because jump will be formed at the toe of structure).

CLASSIFICATION OF HYDRAULIC JUMP

Type of hydraulic jump is defined based on Froude’s number,

i) FN = 1.0 No jump

ii) FN = 1.0 – 1.7 Undulated jump/Roller type jump

iii) FN = 1.7 – 2.5 Weak jump

iv) FN = 2.5 – 4.5 Oscillating jump

v) FN = 4.5 – 9.0 Steady jump

vi) FN > 9.0 Strong jump

y2 d2 U/S

D/S


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PROCEDURE

Adjust the S-6 Tilting flume at a slope and check if there is any problem in arrangement or

anything residual inside the flume causing obstruction in flow.

Setup a specific discharge in the flume.

Note down the depth of the water surface before, after and at the hydraulic jump.

Repeat the above procedure with by increasing discharge.

Complete the table of observations and calculations and plot the water surface profile for all

discharges.

PRECAUTIONS


flume.



The reading measurement at the hydraulic jump is difficult, so note the flow carefully and take

the reading at desired point.


30 2008-CIVIL-87

OBSERVATION & CALCULATION:

Width of Flume -0.3 m

SR.

#

Discharge

Q

(m3/sec)

Depth of Flow (m) Horizontal

Distances (m) yc

(m)

Height

of

Jump

Hj

(y2-y1)

(m)

Length

of

Jump

(x2-x1)

(m)

Loss of

Energy

at jump

hL (m)

V1 =

Q/(B.y1)

(m/sec)

FN1 Type of

Jump

Theoretical Sequent

Depth (y2) m

(yo) (y1) (y2) (xo) (x1) (x2)

1 0.000798 0.0227 0.02 0.076 2 3.982 4.13 0.009 0.056 0.145 0.028884 0.133 0.3 Roller

type jump 0.0084

2 0.010925 0.0275 0.0236 0.0847 2 4.112 4.36 0.051 0.0611 0.252 0.028528 1.543079096 3.21 Oscillating

Jump 0.0491

3 0.012326 0.03 0.026 0.0936

2 4.206 4.46

0.056 0.0676 0.252 0.031734 1.58025641 3.13 Oscillating

Jump 0.0533

4 0.013853 0.0327 0.0298 0.0938 2 4.302 4.58 0.06 0.064 0.282 0.023446 1.549552573 2.87 Oscillating

Jump 0.0580

5 0.015228 0.0361 0.0323 0.0995 2 4.386 4.68 0.064 0.0672 0.291 0.023606 1.571517028 2.79 Oscillating

Jump 0.0619

6 0.016488 0.0391 0.035 0.107 2 4.63 4.79 0.068 0.072 0.159 0.024916 1.570285714 2.68 Oscillating

Jump 0.0654


31 2008-CIVIL-87

HYDRAULIC JUMP PROFILES:

1st Observation:

2nd

Observation:

0

0.02

0.04

0.06

0.08

0.1

0.12

1.5 2.5 3.5 4.5

De

pth

of

Flo

w (

y) (

m)

Horizontal Distance (x) (m)

1st Observation

0

0.02

0.04

0.06

0.08

0.1

0.12

1.5 2.5 3.5 4.5 5.5

De

pth

of

Flo

w (

y) (

m)


2nd Observation

YC


32 2008-CIVIL-87

3rd

Observation:

4th

Observation:

0

0.02

0.04

0.06

0.08

0.1

0.12

1.5 2.5 3.5 4.5 5.5

De

pth

of

Flo

w (

y) (

m)


3rd Observation

YC

0

0.02

0.04

0.06

0.08

0.1

0.12

1.5 2.5 3.5 4.5 5.5

De

pth

of

Flo

w (

y) (

m)


4th Observation


33 2008-CIVIL-87

5th

Observation:

6th

Observation:

0

0.02

0.04

0.06

0.08

0.1

0.12

1.5 2.5 3.5 4.5 5.5

De

pth

of

Flo

w (

y) (

m)


5th Observation

YC

0

0.02

0.04

0.06

0.08

0.1

0.12

1.5 2.5 3.5 4.5 5.5

De

pth

of

Flo

w (

y) (

m)


6th Observation

YC


34 2008-CIVIL-87

COMMENTS:

According to definition hydraulic jump is formed due to change in slope or change of flow from

super critical to sub critical flow, but in observation 1 there is no change of slope or there is no

change in flow, this might be due to some error while performing experiment.

The reading measurement at the hydraulic jump was difficult as the turbulence was not allowing us

to consider a constant point for observation.

There might be error in depth of flow values due to momentary variation in height of the jump.

Some Water is also flowing under the hump and this may disturb the results adversely.

Documents

Lab Manual (Hydraulics Engineering)