fluid mechanic .malika khalil

1. UNIVERSITYOF DUHOK
COLLEGEOF ENGINEERING
CIVIL ENGINEERING DEPARTMENT
FLUID MECHANIC_PRACTICAL
FLUID MECHANIC
REPORT ABOUT
Graph drawing
SUBMITTED BY: Malika Khalil
LAB.NA. 1
GROUP NAME:
TESTING DATE: 22/10/2015
SUBMITTING DATE:29/10/2015
2015-2016

2. Abstract
This test is used to measure the discharge of the water and make the
relationship between discharge and head of water
Introduction:
Water draining out of a tank, reservoir, or pond is a common situation. Our
calculation allows you to compute the time needed to lower the water from one depth
to a lower depth or to empty the tank. Alternatively, the user can input a time and
choose another variable to be computed - orifice coefficient, orifice diameter or
orifice area, tank diameter or tank area, initial liquid depth, or final liquid depth.
Purpose:
1. To determine the relationship between the variables.
2. To determine the equation relates variables.
Materials:
1. Small tank.
2. Water.
3. Graduate cylinder.
4. Stop watch.

3. Procedures:
1. Firstly we take the tank and full it by water.
2. We record the height of water inside the take.
3. Then we open the tap and we record the time until a small empty
of 2 cm of water.
4. We close the tap and we take the volume of water inside the
cylinder.
5. We determine the discharge from the volume and time.
6. We repeat this procedure for other steps.
Results:
Q=
Volume(ml)
𝑡𝑖𝑚𝑒(sec)
a= (Q2-Q1) / (H2-H2)

4. H(cm) Q=V/T(ml/sec)
1.5 110
2 125
3 150
4 175
5 200
7 230
8 250
Regular grid paper:
𝑄 = 𝑎𝐻 + 𝑏 ,𝑎 = 𝑡𝑎𝑛𝜃 , α =Q2 – Q1/H2 –H1
Log- log paper: Q= KHn
,𝑛 = 𝑡𝑎𝑛𝜃 , n= logQ2 – logQ1/logH2 –logH1

5. Discussion and Conclusions:
We made this test in order to determine the between variables Q and
D, one of the error that we made on experiment was the problem that
we faced with fixing tap because we didn’t closed the tap at the
recorded time, so this what lead to surface tension because we
recorded the upper line of surface tension but the order was the lower
line.
To summarize this point we discovered that how much the level of
water is reducing the level of discharge will be lower, and this will
reduce the level of pressure as well
References:
http://www.lmnoeng.com/Tank/TankTime.php