Bernoulli's Theorem Lab Report

Topics: Fluid dynamics, Bernoulli's principle, Pressure head Pages: 14 (3829 words) Published: March 16, 2013
Laboratory Report Bernoulli’s Theorem
Lubna Khan, BEng Architectural Engineering

Student ID No.: H00113999
Date: 22/12/2012
Lab Experiment held on: 28/11/2012

Summary/Abstract Page 3
1.1. IntroductionPage 4
1.2. ObjectivePage 5
2. TheoryPage 5
2.1. Theoretical BackgroundPage 5
2.1.1. Sample Calculations:Page 8
2.1.1.1. First experimentPage 8
3. EquipmentPage 10
3.1. Preparing the ApparatusPage 10
3.2. Technical DataPage 11
4. Test ProcedurePage 12
4.1. Bernoulli’s Theorem TestPage 12
5. Results and DiscussionsPage 12
5.1. Data SheetPage 13
5.1.1. First ExperimentPage 13
5.1.2. Second ExperimentPage 13
5.1.3. Third ExperimentPage 14
5.2.2. Diff. between Mea. and The. Pressure-Head GraphPage 16
5.2.3. Total Head Loss GraphPage 17
5.2.4. Total Pressure Head GraphPage 18
Conclusion Page 19
ReferencesPage21
Summary/Abstract:
The main objective of this experiment is to verify the Bernoulli Equation using a Venturi meter which is a converging-diverging tube of known geometry which is attached to a pipeline to help measure different quantities of flow rates. Furthermore, different forms of Bernoulli’s Equation is used to calculate pressure head, head loss and velocity loss. After finding out the data, the measured values of the static pressure head for each increasing flow rate is compared with the theoretical value, calculated by the Bernoulli’s equation. The head loss is also found by measuring the 8th manometer on the manometer panel whose difference each time will give the head loss. The difference between the measured and theoretical value of static head is then found out to be due to the frictional losses occurring in the pipe. The head loss which should remain constant also varies slightly due to the mentioned reason. This experiment investigates the benefits and restrictions of Bernoulli’s principle by comparing theoretical and measured values, graphs and different flow rates. Bernoulli’s equation is efficient and important in engineering subjects concerning fluids and systems concerned with fluids laws.

1.1. Introduction:
The Bernoulli’s principle or Bernoulli’s theory states that for an inviscid flow, as the speed or velocity of the fluid increases the pressure of that fluid decreases. This principle was named by Daniel Bernoulli, a Swiss mathematician after himself and published it in his book called Hydrodynamica in 1738. Bernoulli’s Principle is derived from the principle of Conservation of Energy which states that the total energy of the fluid must be same at all points in the streamline of the fluid. This means that the sum of kinetic and potential energy of a mass must remain constant in all stages. The Bernoulli’s principle states the inverse proportion between pressure and velocity of an inviscid flow. However, in reality data shows energy losses due to viscosity caused by the channel’s walls. The Bernoulli’s principle is used to calculate the lift force on an airfoil. Pressure difference caused due to the difference in speeds of air flowing past the top surface (higher) of an aircraft wing and the bottom surface(lower) of the wing results in an upwards lifting force. The Bernoulli’s Equation is then used to find the life forces if the top and bottom speed of the air is known to a good approximation. Also, the airspeed of the aircraft is determined by using the Pitot Tube and Static Port on an aircraft which are connected to the airspeed indicator. This determines the dynamic pressure (difference between stagnation pressure and static pressure) of the airflow past the aircraft, which is calibrated with the help of...