-
8/12/2019 Head Loss in the Pipe Line
1/6
Hydraulics LaboratoryExperiment Report
Name: Ahmed Essam Mansour
Section: "1", Monday 2-5 pm
Title: Head loss in the pipe line
Date: 2 October-2006
-
8/12/2019 Head Loss in the Pipe Line
2/6
Objectives:
To determine the head loss and friction factor for laminar
andturbulent flow in a smooth pipe over a range of Reynolds
number.
To find the relationship between Head loss and the velocity
offlow, and between the friction factor and the Reynolds
number.
Theory:
When liquids flow in circular pipes, losses in energy occur due
to
frictional resistance at the pipe's wall. The energy losses are
measured bytheHead Loss"hL" , and the frictional resistance is
evaluated by using a
parameter called the Friction Factor " f ".
The Head Loss "hL" is generally measured using Darcy's
Equation;
And its relation to the velocity of flow depends on the type of
flow
specified by Reynolds number as follows;
The Friction factor "f " of a flow depends on two parameters;
the
Reynolds number and the Relative roughness of a pipe's wall.
As we are dealing with a smooth pipe in this experiment the
second
parameter will be neglected and the friction factor will be
evaluated as
follows;
-
8/12/2019 Head Loss in the Pipe Line
3/6
Reynolds number depend mainly on the velocity of flow and
the
properties of the fluid, and is evaluated using the formula;
Reynolds number is used to distinguish between two main regions
in flow
i.e. Turbulent flow (Re > 4000) and Laminar flow (Re <
2000).
Experimental measurements will include the measurement of the
weight
of oil in a specified time, which will be used to calculate the
flow rate
from which the velocity will be determined;
And the Heads at two point on the pipe with a know distance
betweenthem to be used to find the head loss "hL" along that
distance.
This head loss is measured by mercury manometers, so the
equivalent
value for head loss in oil is found by;
Then the experimental value of the friction factor is to be
measured "f "
by using Darcy;s equation specified above.
-
8/12/2019 Head Loss in the Pipe Line
4/6
Apparatus:Procedures:
1. Run the apparatus for few minutes to warm up the motor
andensure steady conditions.
2. When the flow was steady, the reading of h10 and h18 were
takenand the time of filling a know weight of oil was recorded.
3. A series of trials were done by taking different hL and flow
rate.
Results:
-
8/12/2019 Head Loss in the Pipe Line
5/6
Weight
(kg)
Time
(s)
Q
(m3/s)
V
(m/s)
HL forHg
HLfor
Oil
f
(exp)
f
(theo)Re
10 1.29
10 0.32
10 0.52
20 1.07
20 0.40
20 0.41
30 0.47
30 0.26
30 0.23
Conclusions:
-
8/12/2019 Head Loss in the Pipe Line
6/6
As noticed from the tabulated data, there are several errors
that caused
unexpected results;
From the series trails done, the rate of flow was disordered as
itwas supposed to increase in each trial.
The differences between the theoretical and experimental results
ofthe friction factor are large.
These errors may be returned to misreading the apparatus and to
the
weight device which causes problems during the experiment.
The head loss increases as the velocity of flow increase and
this accepts
the theoretical concepts.
