LABORATORY OUTCOME BASED ASSESSMENT GUIDELINE
TOPIC EXPERIMENT: BERNOULLI THEOREM
PROGRAM LEARNING OUTCOMES (PLO)Upon completion of the programme, graduates will be able to:1 Possesses and apply civil engineering knowledge2 Demonstrate technical skills in civil engineering3 Understand and commit professionally , ethically and humane responsibility, in line the code of
conduct4 Communicate effectively both in written and spoken form with other colleague and community5 Identify and provide creative, innovative and effective solution to civil engineering problems6 Recognise the need and to engage in, lifelong learning and professional development7 Self motivate and enhance entrepreneurship skill for career development8 Demonstrate leaderships skills to lead a team9 Work collaboratively as team members
COURSE LEARNING OUTCOMES (CLO) Upon completion of this course, students should be able to:- 1. Explain clearly the fluid characteristics, fluid pressure and solve problems in flow of fluid using
Bernoulli’s Equation.2. Apply principles to solve problems in laminar and turbulent flow and relation to Reynolds number, Darcy’s and Hagen-Poiseuille equation for problem solving.3. Apply correct methods and procedures of hydraulics solution towards practical problems.4. Acquire appropriate knowledge in minor loss in pipe and uniform flow in open channel
No. Lab.TitleTeachingMethod
PLO CLO GSA / LD
1.0Fluid Characteristics
Lecture,Q&A,
Demo AndLabo.
1&2 3 LD1 & LD 2
2.0Bernoulli Theorem
3.0Reynolds Number
4.0Fluid Friction Test
5.0Uniform Flow
Generic Student Attributes (GSA): GSA 1 Communications Skills GSA 2 Critical Thinking and Problem Solving Skills GSA 3 Teamwork Skills GSA 4 Moral and Professional Ethics GSA 5 Leadership Skills GSA 6 Information Management Skills and
Continuous Learning GSA 7 Entrepreneurship Skills
Learning Domain (LD):LD 1 Knowledge LD 2 Technical Skills LD 3 Professionalism and Ethics LD 4 Social Skills and
Responsibilities LD 5 Communication Skills LD 6 Critical Thinking LD 7 Life Long Learning LD 8 Entrepreneurial Skills LD 9 Teamwork / Leadership Skills
NO. EXPERIMENT : 2
TOPIC EXPERIMENT : BERNOULLI THEOREM
INTRODUCTION :
This experiment is carried out to investigate the validility of Bernoulli’s theorem
when applied to the steady flow of water in tapered duct and total pressure heads
in a rigid convergent/divergent tube of known geometry for range of steady flow
rates . The Bernoulli’s theorem relates the pressure , velocity and elevation in a
moving fluid ( liquid or gases ) , the compressibility and viscosity ( Internal friction )
which are negligible and the flow of which is steady , or laminar .
Bernoulli's principle can be applied to various types of fluid flow, resulting in what is
loosely denoted as Bernoulli's equation. In fact, there are different forms of the
Bernoulli equation for different types of flow. The simple form of Bernoulli's
principle is valid for incompressible flows (e.g. most liquid flows) and also for
compressible flows (e.g. gases) moving at low Mach numbers (usually less than
0.3). More advanced forms may in some cases be applied to compressible flows at
higher Mach numbers (see the derivations of the Bernoulli equation). Bernoulli's
principle can be derived from the principle of conservation of energy. This states
that, in a steady flow, the sum of all forms of mechanical energy in a fluid along a
streamline is the same at all points on that streamline. This requires that the sum
of kinetic energy and potential energy remain constant.
OBJECTIVE : To investigate the validity of Bernoulli’s Theorem
and Pressure measurements along venturi tube.
APPARATUS : Hydraulic bench
Bernoulli’s Theorem Demonstration apparatus.
Stop watch
Figure 1: Bernoulli’s Theorem Demonstration Apparatus
1. Assembly board
2. Single water pressure gauge
3. Discharge pipe
4. Outlet ball cock
5. Venturi tube with 6 measurement points
6. Compression gland
7. Probe for measuring overall pressure (can be moved axially)
8. Hose connection, water supply
9. Ball cock at water inlet
10. 6-fold water pressure gauge (pressure distribution in venture tube)
THEORY :
The measured values are to be compared to Bernoulli’s equation.
Bernoulli’s equation for constant head h:
Allowance for friction losses and conversion of the pressures p1 and p2 into static
pressure heads h1 and h2 yields:
p1 = Pressure at cross-section A1
h1 = Pressure head at cross-section A1
v1 = Flow velocity at cross-section A1
p2 = Pressure at cross-section A2
h2 = Pressure head at cross-section A2
v2 = Flow velocity at cross-section A2
= Density of medium = constant for incompressible fluids
such as water
hv = Pressure loss head
The venturi tube used has 6 measurement points. The table below shows the
standardised reference velocity . This parameter is derived from the geometry of
the venturi tube.
Point, i di (mm)
1 28.4
2 22.5
3 14.0
4 17.2
5 24.2
6 28.4
Multiplying the reference velocity values with a starting value, the student can
calculate the theoretical velocity values vcalc at the 6 measuring points of the venturi
tube.
At constant flow rate, the starting value for calculating the theoretical velocity is
found as:
The results for the calculated velocity, vcalc can be found in the table.
Calculation of dynamic pressure head:
80 mm must be subtracted, as there is a zero-point difference of 80 mm between
the pressure gauges.
The velocity, vmeas was calculated from the dynamic pressure
A
CONCLUSION
Bernoulli's principle can be used to calculate the lift force on an airfoil if the
behaviour of the fluid flow in the vicinity of the foil is known. For example, if the air
flowing past the top surface of an aircraft wing is moving faster than the air flowing
past the bottom surface, then Bernoulli's principle implies that the pressure on the
surfaces of the wing will be lower above than below. This pressure difference
results in an upwards lifting force. Whenever the distribution of speed past the top
and bottom surfaces of a wing is known, the lift forces can be calculated (to a good
approximation) using Bernoulli's equations established by Bernoulli over a century
before the first man-made wings were used for the purpose of flight. Bernoulli's
principle does not explain why the air flows faster past the top of the wing and
slower past the underside. To understand why, it is helpful to understand
circulation, the Kutta condition, and the Kutta–Joukowski theorem.
The carburetor used in many reciprocating engines contains a venturi to create a
region of low pressure to draw fuel into the carburetor and mix it thoroughly with
the incoming air. The low pressure in the throat of a venturi can be explained by
Bernoulli's principle; in the narrow throat, the air is moving at its fastest speed and
therefore it is at its lowest pressure.
The Pitot tube and static port on an aircraft are used to determine the airspeed of
the aircraft. These two devices are connected to the airspeed indicator, which
determines the dynamic pressure of the airflow past the aircraft. Dynamic pressure
is the difference between stagnation pressure and static pressure. Bernoulli's
principle is used to calibrate the airspeed indicator so that it displays the indicated
airspeed appropriate to the dynamic pressure