VENTURI FLOW CHARACTERISTICS
OBJECTIVES:
To understand and provide the theory of how a venture works. To measure the flow through and differential pressure across a Venturi flow meter. To plot the pressure profiles across a Venturi at a different flow rates. To examine and discuss the relationship between flow and ∆P through a Venturi in a pipe at a various distances from the Venturi.
THEORY:
The Venturi flow meter is an equipment that uses the Bernoulli Effect and a manometer pressure gauge to measure the rate of flow of a liquid or fluid that is flowing through a pipe. There is also a part in the venture equipment that has a reduced cross-sectional area. When the liquid goes through this part, the speed (velocity) tend to …show more content…
The principle in Venturi piping is based on the Bernoulli’s equation. The different pressure between inside of the venturi meter is created by reducing the cross-sectional area of the flow. This pressure will be converted to energy, as a velocity. We can observe the difference of pressure measured by using a different U-tube manometer (A-D). The pressure difference allows to determine the rate of fluid or discharging flow through the pipe line. Since the inlet venturi is larger than throat venturi, it leads the increasing of velocity at the throat, resulting in decrease of pressure. As a result, we can see the different level between the tubes, which means the pressure difference between the inlet and the throat of the venturi. . In our experiment, the lowest pressure was measured at manometer D where it’s the least cross sectional area at the point. As the area of cross section increased the total kinetic energy was converted to pressure.at the manometer tube K some of the differential pressure was …show more content…
The differential pressures obtained were less than 185, 165, 140, 125, 105 mm of H2O instead of 250, 200, 150, 100, and 50 in the beginning due to the air bubbles trapped within the manometer tubes. This lead to abnormal recovery in pressures.
3. The energy will be lost through a Venturi meter because Venturi meters do consume energy. Vibration, noise or can lose the material also had contributed to the same.
4. We can observe the result from the table that as a differential pressure of mm H2O increases, the flow rate also increases. As a result, we can confirm the result theoretically from Bernoulli’s equation.
5. In the Venturi meter, as the velocity is increased, pressure is decreased, and pressure difference will be utilized to measure the rate of flow. After the pressure difference is generated, the fluid is passed through a pressure recovery exit section. In this section, the 80% of the differential pressure generated at the constricted area, will be recovered. However, in the Orifice plate, all of the pressure loss is not recovered because of friction and turbulence losses in the