Republic of the Philippines

BATANGAS STATE UNIVERSITY

Civil and Sanitary Engineering Department

CE 410
HYDRAULICS

Laboratory Experiment 1

VENTURI METER
Laboratory Report

Submitted by:
Arellano, Nicole Ann R.
Delag, Louise Lane R.
Gonzales, Gemma R.
Lasco, Paul Vincent L.

Submitted to:
Engr. Vivian D. Guda
 Republic of the Philippines
BATANGAS STATE UNIVERSITY
Alangilan Campus, Batangas City
COLLEGE OF ENGINEERING, ARCHITECTURE & FINE ARTS
https://batstate-u.edu.ph/, Tel. No. (043) 425-0139 loc. 118/2121

Civil and Sanitary Engineering Department

Introduction
The main objective of this experiment is to determine the discharge coefficient of
a specific venturi meter. To do so, a venturi meter is required; this is a flow measurement
instrument based on Bernoulli's equation. According to Mishra 2016, “Bernoulli’s
Statement states that it is in a steady, ideal flow of an incompressible fluid, the total
energy at any point of the fluid is constant. The total energy consists of pressure energy,
kinetic energy and potential energy or datum energy”.
Venturi meters are flow measuring instruments that utilize a converging section of
pipe to increase the flow velocity and create a matching pressure drop from which the
flow rate can be calculated (Reader-Hariss, 2011). Within the pipe, the pressure
difference is established by narrowing the flow passage's cross-sectional area. With the
help of a manometer, this pressure difference is measured, which aids in establishing the
rate of fluid flow or other discharge from the pipeline. The flow rate can be calculated by
measuring the pressure difference between the venture inlet and neck.
The venturi meter comprises three essential components: First, a small converging
section: This is the part of the venturi where the fluid converges; Second, the throat: This
is the part of the venturi between the converging-diverging parts. The throat's cross-
section is substantially smaller than that of the converging and diverging sections. As the
fluid enters the throat, its velocity increases while its pressure lowers; Finally, the
diverging part is the section of the venturi meter where the fluid diverges.
 Republic of the Philippines
BATANGAS STATE UNIVERSITY
Alangilan Campus, Batangas City
COLLEGE OF ENGINEERING, ARCHITECTURE & FINE ARTS
https://batstate-u.edu.ph/, Tel. No. (043) 425-0139 loc. 118/2121

Civil and Sanitary Engineering Department

Materials and Methodology

 Venturi Meter
 Differential Manometer
 Collecting tank
 Piezometer
 Stopwatch
 Measuring scale

Procedure:
1. A pipe with a 50 mm diameter is selected and opened first.
2. To allow the flow of water in the 50 mm diameter pipe, the main inlet valve of
the venturi meter is opened as well as the pipe inlet valve. Now, to remove the
air inside the pipe to prevent the air bubbles, the knot of manometer is then
change from isolate position to air – vent position.
3. As the knob of manometer is kept in the read position, the left limb and right
limb readings from the manometer is noted down in order to obtain the head
loss.
4. A constant water flow is made which is now able to flow through the selected
50 mm diameter pipe of venturi meter. The current flow rate will help in
determining the difference in pressure between the inlet and throat. The tank
outlet valve is then closed to measure the discharge.
5. The exit valve of the collecting tank is closed and the time taken by the tank
water to rise using the stopwatch is noted.
6. Finally, after gathering all the necessary information from the readings and
given data through the observation made, the calculation of actual and
theoretical discharge as well as the coefficient of discharge will take place.
This procedure goes the same way for the subsequent trials.
 Republic of the Philippines
BATANGAS STATE UNIVERSITY
Alangilan Campus, Batangas City
COLLEGE OF ENGINEERING, ARCHITECTURE & FINE ARTS
https://batstate-u.edu.ph/, Tel. No. (043) 425-0139 loc. 118/2121

Civil and Sanitary Engineering Department

Results

Discussions and Conclusions