ABDULLAH GUL UNIVERSITY
DEPARTMENT OF CIVIL
ENGINEERING
CE 272 FLUID MECHANICS
Dr. A. Ersin Dinçer
CE 272 FLUID MECHANICS DEPARTMENT OF CIVIL ENGINEERING ABDULLAH GUL UNIVERSITY 2018-2019 SPRING
1 - INTRODUCTION
After completing this chapter, you should be able to:
• Determine the dimensions and units of physical quantities.
• Identify the key fluid properties used in the analysis of fluid behavior.
• Calculate common fluid properties given appropriate information.
• Explain effects of fluid compressibility.
• Use the concepts of viscosity, vapor pressure, and surface tension.
CE 272 FLUID MECHANICS DEPARTMENT OF CIVIL ENGINEERING ABDULLAH GUL UNIVERSITY 2018-2019 SPRING
1 - INTRODUCTION
Question
How do you distinguish a solid and a fluid?
CE 272 FLUID MECHANICS DEPARTMENT OF CIVIL ENGINEERING ABDULLAH GUL UNIVERSITY 2018-2019 SPRING
1 - INTRODUCTION
1.1. Definition of Fluid
Matter exists in 3 states in nature:
(a) Solid State:
The molecules in a
solid are arranged in a
pattern that is
repeated throughout.
(c) Gaseous State:
(b) Liquid State:
In liquids molecules
can rotate and
translate freely.
In the gas phase, the
molecules are far apart
from each other, and
molecular ordering is
nonexistent.
CE 272 FLUID MECHANICS DEPARTMENT OF CIVIL ENGINEERING ABDULLAH GUL UNIVERSITY 2018-2019 SPRING
1 - INTRODUCTION
1.1. Definition of Fluid
•
A fluid is a substance which deforms continuously under the application of a
shearing stress, no matter how small the shearing stress is.
•
A solid, on the other hand, will deform by an amount proportional to the
stress applied, after which static equilibrium will result.
CE 272 FLUID MECHANICS DEPARTMENT OF CIVIL ENGINEERING ABDULLAH GUL UNIVERSITY 2018-2019 SPRING
1 - INTRODUCTION
1.1. Definition of Fluid
For fluids;
Since the deformation in fluids is continuous, we talk about the rates of
deformation, rather than the deformation itself.
CE 272 FLUID MECHANICS DEPARTMENT OF CIVIL ENGINEERING ABDULLAH GUL UNIVERSITY 2018-2019 SPRING
1 - INTRODUCTION
1.1. Definition of Fluid
Therefore, the fluids at rest can not contain shearing stresses, no component of
stress can exist in a static fluid tangent to a solid boundary, or tangent to an
arbitrary section passed through the fluid.
This means that the forces in static fluids must be transmitted to solid
boundaries or arbitrary sections normal to these boundaries, or sections at every
point.
In other words, if there exists shear stresses, then the fluid must be in motion.
CE 272 FLUID MECHANICS DEPARTMENT OF CIVIL ENGINEERING ABDULLAH GUL UNIVERSITY 2018-2019 SPRING
1 - INTRODUCTION
1.1. Definition of Fluid
What is the difference between a solid and a fluid?
Simple definition: A solid is “hard” and not easily deformed, whereas a fluid is
“soft” and is easily deformed.
A closer look at the molecular structure of materials reveals that;
A solid such as steel, concrete, has densely spaced molecules with large
intermolecular cohesive forces that allow the solid to maintain it’s shape, and to
not be easily deformed.
A liquid such as water, oil, the molecules are spaced farther apart, the
intermolecular forces are smaller than for solids, and the molecules have more
freedom of movement.
CE 272 FLUID MECHANICS DEPARTMENT OF CIVIL ENGINEERING ABDULLAH GUL UNIVERSITY 2018-2019 SPRING
1 - INTRODUCTION
1.1. Definition of Fluid
Thus, liquids can be easily deformed but not easily compressed and can be
poured into containers or forced through a tube.
Fluids
{
Gases air, oxygen, have even greater
molecular spacing and freedom of
motion with negligible cohesive
intermolecular forces and as a
consequence are easily deformed
and compressed and will completely
fill the volume of any container in
which they are placed.
Both liquids and gases are fluids.
CE 272 FLUID MECHANICS DEPARTMENT OF CIVIL ENGINEERING ABDULLAH GUL UNIVERSITY 2018-2019 SPRING
1 - INTRODUCTION
1.2. Definition of Fluid Mechanics
MECHANICS
is the oldest physical science that deals with both stationary and
moving bodies under the influence of forces.
STATICS
DYNAMICS
is the branch of mechanics that
deals with bodies at rest.
is the branch of mechanics that
deals with bodies in motion.
CE 272 FLUID MECHANICS DEPARTMENT OF CIVIL ENGINEERING ABDULLAH GUL UNIVERSITY 2018-2019 SPRING
1 - INTRODUCTION
1.2. Definition of Fluid Mechanics
FLUID MECHANICS
is dealing with behavior of fluids and the interaction of fluids with
solids or other fluids at the boundaries.
FLUID STATICS
FLUID DYNAMICS
is the branch of fluid mechanics
that deals with fluids at rest.
is the branch of fluid mechanics
that deals with fluids in motion.
CE 272 FLUID MECHANICS DEPARTMENT OF CIVIL ENGINEERING ABDULLAH GUL UNIVERSITY 2018-2019 SPRING
1 - INTRODUCTION
1.2. Definition of Fluid Mechanics
Fluid mechanics is the discipline that is concerned with the behavior of liquids
and gases at rest or in motion.
It covers a vast array of phenomena that occur in nature (with or without human
intervention), in biology, and in numerous engineered, invented, or
manufactured situations.
CE 272 FLUID MECHANICS DEPARTMENT OF CIVIL ENGINEERING ABDULLAH GUL UNIVERSITY 2018-2019 SPRING
1 - INTRODUCTION
1.2. Definition of Fluid Mechanics
Fluid Mechanics In Everyday Life
Materials
Science
Biology
Aerospace
Mechanical
Engineering
Chemistry
Medicine
Fluid
Mechanics
In my life
as well…
Civil
Engineering
CE 272 FLUID MECHANICS DEPARTMENT OF CIVIL ENGINEERING ABDULLAH GUL UNIVERSITY 2018-2019 SPRING
1 - INTRODUCTION
1.3. Fluid Mechanics in Civil Engineering
CE 272 FLUID MECHANICS DEPARTMENT OF CIVIL ENGINEERING ABDULLAH GUL UNIVERSITY 2018-2019 SPRING
1 - INTRODUCTION
1.4. Fluid Mechanics History
CE 272 FLUID MECHANICS DEPARTMENT OF CIVIL ENGINEERING ABDULLAH GUL UNIVERSITY 2018-2019 SPRING
1 - INTRODUCTION
1.4. Fluid Mechanics History
Archimedes (C.287-212 BC)
Archimedes develops the law of buoyancy, also known as Archimedes' Principle.
CE 272 FLUID MECHANICS DEPARTMENT OF CIVIL ENGINEERING ABDULLAH GUL UNIVERSITY 2018-2019 SPRING
1 - INTRODUCTION
1.4. Fluid Mechanics History
Newton (1642-1727)
The effects of friction and viscosity in diminishing the velocity of running water
were noticed in the Principia of Sir Isaac Newton.
CE 272 FLUID MECHANICS DEPARTMENT OF CIVIL ENGINEERING ABDULLAH GUL UNIVERSITY 2018-2019 SPRING
1 - INTRODUCTION
1.4. Fluid Mechanics History
Bernoulli (1667-1748)
Daniel Bernoulli found that an increase in the speed of a fluid occurs
simultaneously with a decrease in pressure or a decrease in the fluid's
potential energy.
Pressure
Head
Static
Head
Velocity
Head
+
Total
Head
+
=
CE 272 FLUID MECHANICS DEPARTMENT OF CIVIL ENGINEERING ABDULLAH GUL UNIVERSITY 2018-2019 SPRING
1 - INTRODUCTION
1.4. Fluid Mechanics History
Euler (1707-1783)
The resolution of the questions concerning the motion of fluids was effected by
means of Leonhard Euler's partial differential coefficients.
CE 272 FLUID MECHANICS DEPARTMENT OF CIVIL ENGINEERING ABDULLAH GUL UNIVERSITY 2018-2019 SPRING
1 - INTRODUCTION
1.4. Fluid Mechanics History
Navier
(1785-1836)
Stokes
(1819-1903)
Navier–Stokes equations named after
Claude-Louis Navier and George Gabriel
Stokes, describe the motion of viscous
fluid substances.
Navier–Stokes equations is one of the The
Millennium Prize Problems that were stated by the
Clay Mathematics Institute in 2000. A correct
solution to any of the problems results in a US $1
million prize being awarded by the institute to the
discoverer(s).
CE 272 FLUID MECHANICS DEPARTMENT OF CIVIL ENGINEERING ABDULLAH GUL UNIVERSITY 2018-2019 SPRING
1 - INTRODUCTION
1.4. Fluid Mechanics History
Reynolds (1842-1912)
Reynolds most famously studied the conditions in which the flow of fluid in
pipes transitioned from laminar flow to turbulent flow.
CE 272 FLUID MECHANICS DEPARTMENT OF CIVIL ENGINEERING ABDULLAH GUL UNIVERSITY 2018-2019 SPRING
1 - INTRODUCTION
1.5. Fluid Flow Parameters
Three of the important parameters that
describe fluid flow:
(1) The physical size of the flow, ℓ;
(2) The velocity of the flow, V; and
(3) The pressure, p, as indicated in the figure for a
light aircraft parachute recovery system.
CE 272 FLUID MECHANICS DEPARTMENT OF CIVIL ENGINEERING ABDULLAH GUL UNIVERSITY 2018-2019 SPRING
1 - INTRODUCTION
1.5. Fluid Flow Parameters
Size, 𝒍;
Every flow has a characteristic length associated with it. For example, for flow of
fluid within pipes, the pipe diameter is a characteristic length. Pipe flows include
the flow of water in the pipes in our homes, the blood flow in our arteries and
veins, and the air flow in our bronchial tree.
CE 272 FLUID MECHANICS DEPARTMENT OF CIVIL ENGINEERING ABDULLAH GUL UNIVERSITY 2018-2019 SPRING
1 - INTRODUCTION
1.5. Fluid Flow Parameters
Velocity, V;
As we note from the The Weather Channel, on a given day the wind speed (or
velocity?) may cover what we think of as a wide range, from a gentle 8 km/h
breeze to a 160 km/h hurricane or a 400 km/h tornado.
However, this speed range is
small compared to that of the
almost imperceptible flow of
the fluid-like magma below the
earth’s surface which drives the
motion of the tectonic plates at
a speed (or velocity?) of about
2x10-8 m/s or the 3x104 m/s
hypersonic air flow past a
meteor as it streaks through
the atmosphere.
CE 272 FLUID MECHANICS DEPARTMENT OF CIVIL ENGINEERING ABDULLAH GUL UNIVERSITY 2018-2019 SPRING
1 - INTRODUCTION
1.5. Fluid Flow Parameters
Pressure , P;
The pressure within fluids covers an extremely wide range of values. We are
accustomed to:
- The standard 101325 Pa atmospheric pressure.
- The 35 psi (pounds per square inch) pressure within our car’s tires,
- The “120 over 70” mm-Hg typical blood pressure reading, or
CE 272 FLUID MECHANICS DEPARTMENT OF CIVIL ENGINEERING ABDULLAH GUL UNIVERSITY 2018-2019 SPRING
1 - INTRODUCTION
1.5. Fluid Flow Parameters
Characteristic values of
some
fluid
flow
parameters
for
a
variety of flows:
(a) Object size,
(b) Fluid velocity,
(c) Fluid pressure.
CE 272 FLUID MECHANICS DEPARTMENT OF CIVIL ENGINEERING ABDULLAH GUL UNIVERSITY 2018-2019 SPRING
1 - INTRODUCTION
1.6. Concept of Continuum
Atoms are widely spaced in the gas phase. However, we can disregard the
atomic nature of a substance. View it as a continuous, homogeneous matter
with no holes, that is, a continuum. This allows us to treat properties as
smoothly varying quantities.
CE 272 FLUID MECHANICS DEPARTMENT OF CIVIL ENGINEERING ABDULLAH GUL UNIVERSITY 2018-2019 SPRING
1 - INTRODUCTION
1.6. Concept of Continuum
Continuum is valid as long as size of the system is large in comparison to
distance between molecules.
CE 272 FLUID MECHANICS DEPARTMENT OF CIVIL ENGINEERING ABDULLAH GUL UNIVERSITY 2018-2019 SPRING
1 - INTRODUCTION
1.6. Concept of Continuum
At the microscopic scale, fluids are composed of molecules.
Is it possible to keep track of all these molecules ?
Practically impossible and not necessary for most engineering problems.
Rather, we study most engineering problems at the macroscopic scale. That is
we treat fluids as continuum and do not concern with the behavior of individual
molecules.
CE 272 FLUID MECHANICS DEPARTMENT OF CIVIL ENGINEERING ABDULLAH GUL UNIVERSITY 2018-2019 SPRING
1 - INTRODUCTION
1.6. Concept of Continuum
Microscopic level: Each fluid molecule
shown below moves at a different
speed in a different direction.
Macroscopic level: The speed at point
A is 60 km/hr. The direction of air
flow at point A is as shown below.
60 km/hr is the average speed of molecules in the small volume surrounding
point A. We can say that the fluid particle located at point A is moving with a
speed of 60 km/hr.
CE 272 FLUID MECHANICS DEPARTMENT OF CIVIL ENGINEERING ABDULLAH GUL UNIVERSITY 2018-2019 SPRING
1 - INTRODUCTION
1.6. Concept of Continuum
Continuum assumes that fluid and flow properties, such as density, velocity,
pressure, temperature, etc. vary continuously throughout the fluid.
In continuum, the smallest element of a fluid is NOT a fluid molecule, but rather
a fluid particle, which contains enough number of molecules to make
meaningful statistical averages.
CE 272 FLUID MECHANICS DEPARTMENT OF CIVIL ENGINEERING ABDULLAH GUL UNIVERSITY 2018-2019 SPRING
1 - INTRODUCTION
1.6. Concept of Continuum
Question: Is continuum a reasonable assumption?
• Practical answer: Yes, in many engineering problems.
• Detailed answer: Depends on the Knudsen number.
Continuum is known to be valid for 𝐾𝑛 < 0.01.
In this course we will always treat fluids as continuum.
CE 272 FLUID MECHANICS DEPARTMENT OF CIVIL ENGINEERING ABDULLAH GUL UNIVERSITY 2018-2019 SPRING
1 - INTRODUCTION
1.7. Classification of Fluids
There are many ways to classify fluid flow problems:
Viscous Flow
Internal Flow
Compressible Flow
Laminar Flow
Natural Flow
Steady Flow
One, Two Dimensional Flows
Inviscid Flow
External Flow
Incompressible Flow
Turbulent Flow
Forced Flow
Unsteady Flow
Three-Dimensional Flows
CE 272 FLUID MECHANICS DEPARTMENT OF CIVIL ENGINEERING ABDULLAH GUL UNIVERSITY 2018-2019 SPRING
1 - INTRODUCTION
1.8. System and Control Volume
A system is a collection of matter of fixed identity always the same atoms or fluid
particles, which may move, flow, and interact with its surroundings. The word
system refers to a fixed mass with a boundary. However, with time the boundary
of the system may change, but the mass remains the same.
CE 272 FLUID MECHANICS DEPARTMENT OF CIVIL ENGINEERING ABDULLAH GUL UNIVERSITY 2018-2019 SPRING
1 - INTRODUCTION
1.8. System and Control Volume
The usual example given is that of a piston-cylinder arrangement. Consider a gas
filled in the cylinder which is closed by a piston at the right-hand end. Let us
define gas as our system. If the piston is now operated by pushing or pulling it
the gas compresses or expands. The boundary of our system moves. But the
mass does not move out of the boundary since by definition system is a fixed
mass. The definition does not prevent work or energy crossing the boundary.
CE 272 FLUID MECHANICS DEPARTMENT OF CIVIL ENGINEERING ABDULLAH GUL UNIVERSITY 2018-2019 SPRING
1 - INTRODUCTION
1.8. System and Control Volume
A control volume, on the other hand, is a volume in space a geometric entity,
independent of mass through which fluid may flow.
Here we do not focus our attention on a fixed mass of fluid. Instead, we
establish a "window" for observation in the flow. As against the system, a
control volume has a fixed boundary. Mass, momentum and energy are allowed
to cross the boundary. The shape of the control volume does not change
normally. It is easy to visualize that this is a convenient approach. In fact, it is the
one that is commonly used in fluid dynamics.
CE 272 FLUID MECHANICS DEPARTMENT OF CIVIL ENGINEERING ABDULLAH GUL UNIVERSITY 2018-2019 SPRING
1 - INTRODUCTION
1.8. System and Control Volume
We will consider a fixed control volume most of the time. But it is possible to
have control volumes that change their boundary, those that deform etc.
Obviously, these lead to more complicated equations. The boundary of the
control volume is referred to as control surface.
CE 272 FLUID MECHANICS DEPARTMENT OF CIVIL ENGINEERING ABDULLAH GUL UNIVERSITY 2018-2019 SPRING
1 - INTRODUCTION
1.9. Dimensions and Units
The quantitative description requires both a number and a standard by which
various quantities can be compared. A standard for length might be a meter or
foot, for time an hour or second, and for mass a slug or kilogram.
CE 272 FLUID MECHANICS DEPARTMENT OF CIVIL ENGINEERING ABDULLAH GUL UNIVERSITY 2018-2019 SPRING
1 - INTRODUCTION
1.9. Dimensions and Units
CE 272 FLUID MECHANICS DEPARTMENT OF CIVIL ENGINEERING ABDULLAH GUL UNIVERSITY 2018-2019 SPRING
1 - INTRODUCTION
1.9. Dimensions and Units
SI Units: In 1960, adopted the International System of Units as the
international standard.
BG Units: In the BG system the unit of length is the foot, the time unit is the
second, the force unit is the pound(lb), and the temperature unit is the
degree Fahrenheit.
1 kg= 2.2 lb
CE 272 FLUID MECHANICS DEPARTMENT OF CIVIL ENGINEERING ABDULLAH GUL UNIVERSITY 2018-2019 SPRING
1 - INTRODUCTION
1.9. Dimensions and Units
Dimensional Homogeneity
We all know from grade school that apples
and oranges do not add. But we somehow
manage to do it (by mistake, of course). In
engineering, all equations must be
dimensionally homogeneous. That is, every
term in an equation must have the same
unit. If, at some stage of an analysis, we find
ourselves in a position to add two quantities
that have different units, it is a clear
indication that we have made an error at an
earlier stage. So checking dimensions can
serve as a valuable tool to spot errors.
CE 272 FLUID MECHANICS DEPARTMENT OF CIVIL ENGINEERING ABDULLAH GUL UNIVERSITY 2018-2019 SPRING
1 - INTRODUCTION
1.9. Dimensions and Units
Since the constant ½ is
dimensionless, the equation is
dimensionally homogenous.
Not dimensionally homogenous.
CE 272 FLUID MECHANICS DEPARTMENT OF CIVIL ENGINEERING ABDULLAH GUL UNIVERSITY 2018-2019 SPRING
1 - INTRODUCTION
1.9. Dimensions and Units
EXAMPLE
CE 272 FLUID MECHANICS DEPARTMENT OF CIVIL ENGINEERING ABDULLAH GUL UNIVERSITY 2018-2019 SPRING
1 - INTRODUCTION
1.9. Dimensions and Units
ANSWER
CE 272 FLUID MECHANICS DEPARTMENT OF CIVIL ENGINEERING ABDULLAH GUL UNIVERSITY 2018-2019 SPRING
1 - INTRODUCTION
1.9. Dimensions and Units
EXAMPLE
CE 272 FLUID MECHANICS DEPARTMENT OF CIVIL ENGINEERING ABDULLAH GUL UNIVERSITY 2018-2019 SPRING
1 - INTRODUCTION
1.9. Dimensions and Units
ANSWER
CE 272 FLUID MECHANICS DEPARTMENT OF CIVIL ENGINEERING ABDULLAH GUL UNIVERSITY 2018-2019 SPRING
1 - INTRODUCTION
1.9. Dimensions and Units
EXAMPLE
CE 272 FLUID MECHANICS DEPARTMENT OF CIVIL ENGINEERING ABDULLAH GUL UNIVERSITY 2018-2019 SPRING
1 - INTRODUCTION
1.9. Dimensions and Units
ANSWER
CE 272 FLUID MECHANICS DEPARTMENT OF CIVIL ENGINEERING ABDULLAH GUL UNIVERSITY 2018-2019 SPRING
1 - INTRODUCTION
1.10. Problem Solving Technique
By using a step-by-step approach, an engineer can reduce the solution of a
complicated problem into the solution of a series of simple problems. Most
difficulties encountered while solving a problem are not due to a lack of
knowledge; rather, they are due to a lack of organization.
CE 272 FLUID MECHANICS DEPARTMENT OF CIVIL ENGINEERING ABDULLAH GUL UNIVERSITY 2018-2019 SPRING
1 - INTRODUCTION
1.10. Problem Solving Technique
Step 1: Problem Statement
In your own words, briefly state the problem, the key information given, and the
quantities to be found. This is to make sure that you understand the problem
and the objectives before you attempt to solve the problem.
Step 2: Schematic
Draw a realistic sketch of the physical system involved, and list the relevant
information on the figure. Listing the given information on the sketch helps one
to see the entire problem at once.
Step 3: Assumptions and Approximations
State any appropriate assumptions and approximations made to simplify the
problem to make it possible to obtain a solution. Assume reasonable values for
missing quantities that are necessary. For example, in the absence of specific
data for atmospheric pressure, it can be taken to be 1 atm.
CE 272 FLUID MECHANICS DEPARTMENT OF CIVIL ENGINEERING ABDULLAH GUL UNIVERSITY 2018-2019 SPRING
1 - INTRODUCTION
1.10. Problem Solving Technique
Step 4: Physical Laws
Apply all the relevant basic physical laws and principles (such as the
conservation of mass), and reduce them to their simplest form by utilizing the
assumptions made.
Step 5: Properties
Determine the unknown properties at known states necessary to solve the
problem from property relations or tables. List the properties separately, and
indicate their source, if applicable.
Step 6: Calculations
Substitute the known quantities into the simplified relations and perform the
calculations to determine the unknowns.
Step 7: Reasoning, Verification, and Discussion
Check to make sure that the results obtained are reasonable and intuitive, and
verify the validity of the questionable assumptions. Repeat the calculations that
resulted in unreasonable values.
CE 272 FLUID MECHANICS DEPARTMENT OF CIVIL ENGINEERING ABDULLAH GUL UNIVERSITY 2018-2019 SPRING
1 - INTRODUCTION
1.10. Problem Solving Technique
Keep in mind that the solutions you present to your instructors, and any
engineering analysis presented to others, is a form of communication.
Therefore neatness, organization,
completeness,
and
visual
appearance
are
of
utmost
importance
for
maximum
effectiveness. Besides, neatness
also serves as a great checking tool
since it is very easy to spot errors
and inconsistencies in neat work.
Carelessness and skipping steps to
save time often end up costing
more time and unnecessary
anxiety.
CE 272 FLUID MECHANICS DEPARTMENT OF CIVIL ENGINEERING ABDULLAH GUL UNIVERSITY 2018-2019 SPRING
1 - INTRODUCTION
1.11. Accuracy and Precision
Regardless of the system of units employed, engineers must be aware of three
principles that govern the proper use of numbers: accuracy, precision, and
significant digits.
Accuracy
Agreement of a particular value with the true value. Accurate means "capable
of providing a correct reading or measurement."
Precision
Degree of agreement among several measurements of the same quantity.
What's the difference between accuracy and precision?
https://www.youtube.com/watch?v=hRAFPdDppzs
CE 272 FLUID MECHANICS DEPARTMENT OF CIVIL ENGINEERING ABDULLAH GUL UNIVERSITY 2018-2019 SPRING
1 - INTRODUCTION
1.11. Accuracy and Precision
CE 272 FLUID MECHANICS DEPARTMENT OF CIVIL ENGINEERING ABDULLAH GUL UNIVERSITY 2018-2019 SPRING
1 - INTRODUCTION
1.11. Accuracy and Precision
CE 272 FLUID MECHANICS DEPARTMENT OF CIVIL ENGINEERING ABDULLAH GUL UNIVERSITY 2018-2019 SPRING
1 - INTRODUCTION
1.11. Accuracy and Precision
CE 272 FLUID MECHANICS DEPARTMENT OF CIVIL ENGINEERING ABDULLAH GUL UNIVERSITY 2018-2019 SPRING
1 - INTRODUCTION
1.11. Accuracy and Precision
CE 272 FLUID MECHANICS DEPARTMENT OF CIVIL ENGINEERING ABDULLAH GUL UNIVERSITY 2018-2019 SPRING
1 - INTRODUCTION
1.11. Accuracy and Precision
CE 272 FLUID MECHANICS DEPARTMENT OF CIVIL ENGINEERING ABDULLAH GUL UNIVERSITY 2018-2019 SPRING
1 - INTRODUCTION
1.11. Accuracy and Precision
Evaluate whether the following are precise, accurate or both.
Low Accuracy
Low Precision
Low Accuracy
High Precision
High Accuracy
High Precision
CE 272 FLUID MECHANICS DEPARTMENT OF CIVIL ENGINEERING ABDULLAH GUL UNIVERSITY 2018-2019 SPRING
1 - INTRODUCTION
1.11. Accuracy and Precision
EXAMPLE
a) Who is more accurate when measuring a book that has a true length
of 17.0 cm?
b) Who is more precise when measuring the same 17.0 cm book?
Susan
17.0 cm, 16.0 cm, 18.0 cm, 15.0 cm
Amy:
15.5 cm, 15.0 cm, 15.2 cm, 15.3 cm
CE 272 FLUID MECHANICS DEPARTMENT OF CIVIL ENGINEERING ABDULLAH GUL UNIVERSITY 2018-2019 SPRING
1 - INTRODUCTION
1.11. Accuracy and Precision
End of Chapter-1.
CE 272 FLUID MECHANICS DEPARTMENT OF CIVIL ENGINEERING ABDULLAH GUL UNIVERSITY 2018-2019 SPRING