Here is the finding process of channel depth and channel velocity and critical depth of any preferred area and their graph on the excel

1. University of engineeting and
technology (jalozai campus)
Task:
‘‘Specific energy curve of control
channel’’
Group members:
Farukh Ali
(19jzciv0380)
Sayed shahkar shah
(19jzciv0361)
Section: b semester: 5th
Submitted to: engr. Hazrat amin

2. CONTENT
INTRODUCTION:
SPECIFIC ENERGY
SPECIFIC ENERGY CURVE
TERMINOLOGIES
ASSUMPTIONS
DATA AND CALCULATIONS
RESULTS
COMPARISON OF ACTUAL AND THEORITICAL RESULTS
SITE PICTURE
SITE LOCATION
CONCLUSION

3. Introduction:
WHAT ARE REQUIRED?
 To complete this major assignment, we must determine the Critical depth,
Critical velocity and minimum specific energy of critical depth of a
rectangular channel in a control system.
 Then to plot Specific energy curve, in which the ordinate shows the depth
(y) of the flow and their abscissa represent the specific energy (E) and
locate the “Critical depth (yc), Critical velocity (Vc) and Minimum specific
energy (Emin)” on the graph.
 The estimated values will then be validated by using empirical formulas of
Hydraulic Engineering.
Selected/Performed Area:
The Task was performed on canal of umer banda khawar with the corporation of
irrigation Department Peshawar.
Specific Energy:
The energy per pound of water at any section of a channel measured with respect
to the channel bottom is called specific energy
Taking datum Z=0 as the bottom of the channel, the specific energy E is the sum
of depth of flow (Y) and the velocity head (𝑣2
/2g).
E=y + 𝑣2
/2g
Since v=Q/A, the above can be expressed as,
E= y + 𝑄2
/2g𝐴2

4. SPECIFIC ENERGY CURVE:
When the depth of flow is plotted against specific energy for a given channel
the graph which is obtained is known as specific energy curve.

5. TERMINOLOGIES
MINIMUM SPECIFIC ENERGY:
The point of maximum invert curvature in the graph is known as minimum
specific energy.
Supercritical Depth:
Supercritical depth is below critical depth and having high velocity, supercritical
flow has low potential energy and high kinetic energy.
Critical Velocity:
The velocity at which the specific energy is minimum and having critical depth is
known as critical velocity.
ASSUMPTIONS:
For the particular energy curve, the following presumptions should be considered.
=> Water flows consistently.

6.  The waterway has a slight longitudinal slope, or 1:50,000.
 The distribution of velocity is uniform.

7. RESULTS:
Hence by observing the graph and table, we can conclude with the following
values;
Critical Depth (y) = 0.543 feet
Critical Velocity (V) = 3.66 feet/sec
Minimum Specific Energy (E) = 0.75 feet.
COMPARISON OF ACTUAL & THEORITICAL RESULTS
Theoretical calculations
1) Minimum Specific Energy
As 𝐸𝑚𝑖𝑛=
3
2
𝑦𝑐

8. =
3
2
(0.543)
= 0.81 feet
Hence from the calculated and observed value, it is clear that the minimum
specific energy is equal to 0.75 = 0.8ft.
CRITICAL DEPTH
q=
𝑄
𝑏
=
8.78
4.42
=1.985
As 𝑦𝑐 = √
𝑞2
𝑔
3
Where 𝑦𝑐 = Critical Depth
As 𝑦𝑐 = √
(1.985)2
32.2
3
g= gravitational Constant
= 0.5 feet q= unit discharge
Hence from the calculated and observed value, it is clear that the actual and
theoretical critical depths are almost equal.
Critical Velocity:
As
𝑣𝑐
√𝑔(𝑦𝑐)
= 1
𝑣𝑐 = √𝑔(𝑦𝑐)

9. = √32.2(0.543) = 4.18 feet/sec
We have thus concluded from the calculated and observed result that the real
critical velocity is smaller than the theoretical critical velocity, and the following
are the possible causes of error:
-1) The floating approach, which is not an exact method, was utilized in our
calculations to determine the velocity. The most precise tool for determining
water velocity is a current meter, which is utilized in theoretical calculations.
.2) Another possible explanation for this inaccuracy is because there is no
controlled environment, although in theoretical calculations there is.

10. Google Earth Navigation PIcture:

11. Site pictures

12. CONCLUSION:
1) For any depth more than critical depth (i.e subcritical depth), the velocity will
decrease
2) For any depth less than critical depth (i.e supercritical depth), the velocity will
increase
3) The specific energy increases above and below the critical depth.
4) The two depth (i.e above and below critical depth) having same energy.
referred as alternate depth. having same energy referred as alternate depth.
5) As discharge increases, the specific energy curves move to the upper right
portion