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Lec. 1.1 IntroductionENGR 361 – Fundamentals of Fluid Mechanics
Instructor: Dr. Liangzhu (Leon) Wang
Concordia University
Fall 2011
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Outline
� Course Syllabus
� Fluid Mechanics and Fluids
� Dimension and Unit Systems for Fluids
� Fluid Common Properties
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� Fluid Common Properties
� Basic Equations and Ideal Gas Law
Lectures – Tutorials - Office Hours
� Lectures
Wednesday and Friday 11:45 – 13:00 at SGM FG C080
� Course Website Moodle
� Tutorial Hours
VA: Wednesday 13:15 – 14:05 at SGM FG B030;
VB: Friday 13:15 – 14:05 at SGM FG B030
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VB: Friday 13:15 – 14:05 at SGM FG B030
� Tutors
VA: Adil Chaudhry, [email protected]
VB: Khokan Debnath, [email protected]
Marker: Mehdi Pourabadehei, [email protected]
� Office Hours
Tuesday 13:00 – 15:00 at SGM EV 6.166
Objectives
� This course covers fundamental aspects of fluid
mechanics for junior engineering students. The
objectives are to expose to these students the basic
concepts of fluid and its behavior, the fundamental
physical laws of fluid mechanics, and the application
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physical laws of fluid mechanics, and the application
of these laws in solving engineering problems. As an
introductory course on fluid mechanics, this course
provides the foundation for several subsequent
intermediate and advanced courses in building, civil,
environmental, mechanical and other engineering
disciplines.
Textbooks
� Fundamentals of Fluid Mechanics, Bruce R. Munson,
Donald F. Young, Theodore H. Okiishi, and Wade W.
Huebsch. John Wiley & Sons, Inc., Sixth Edition,
2009. ISBN: 978-0470-26284-9. (Available at the
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2009. ISBN: 978-0470-26284-9. (Available at the
bookstore. One copy reserved at the library)
� Fox and McDonald’s Introduction to Fluid Mechanics,
Philip J. Pritchard. John Wiley & Sons, Inc., Eighth
Edition, 2011. ISBN: 9780470547557.
Tutorials and Homework
� Tutorials are developed to help students understand course materials and work on their homework. Students are expected to attend the tutorials. Tutors will solve similar problems as assigned homework that enables students to work on the problems by
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that enables students to work on the problems by themselves
� The assignment problems will be posted on the course website. Tutorials are provided to help with homework. Students are expected to work on their homework independently. Solutions will be posted at course website.
Exams and Grading
� One midterm (October 7th, 2011) will be given.
Anyone absent for the mid-term exam will be given
zero mark.
� Closed book; Closed notes. ENCS Faculty approved
calculator only. No electronic communication devices
(including cell phones)
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(including cell phones)
� A single-sided letter-sized sheet of paper as a crib
sheet will be allowed in the final exam only.
� Final grade distribution:
Homework: 5%; Midterm: 25%; Final Exam: 70%
� In order to pass this course, the final grade must be
more than 50%.
Learning Skills in ENGR 361
� Problem Analysis – an ability to identify, formulate,
research and solve complex engineering problems
reaching substantial conclusions. This skill will be
taught in the lectures by identifying and solving
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taught in the lectures by identifying and solving
several engineering applications. The students will
practice this skill by solving their assigned homework
problems. This skill will be evaluated using the
performance in the midterm and final examinations.
Other Remarks
� There is no fixed relationship between marks and
letter grades.
� All exams are mandatory and all exams will be
counted.
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counted.
� Events beyond the control of the instructor may
require changes to this outline.
Rights and Responsibilities
� Plagarism
The most common offense under the Academic Code
of Conduct is plagiarism which the Code defines as
“the presentation of the work of another person as
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“the presentation of the work of another person as
one’s own or without proper acknowledgement.”
In Simple Words:
Do not copy, paraphrase or translate anything from
anywhere without saying from where you obtained it!
Sept. 07 – Sept. 09 Chapter 1 Introduction
Sept. 14 – Sept. 21 Chapter 2 Fluid Statics
Sept. 19 DNE Deadline (with tuition refund)
Sept. 23 – Oct. 05 Chapter 3 Elementary Fluid Dynamics
Oct. 7 Midterm Exam
Oct. 10 Thanksgiving day No Class
Oct. 12 – Oct. 19 Chapter 4 Fluid Kinematics
Oct. 21 Discussion and Analysis of Midterm
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Oct. 26 – Nov. 02 Chapter 5 Finite Control Volume Analysis
Oct. 30 DISC Deadline (without tuition refund)
Nov. 4 – Nov. 9 Chapter 6 Differential Analysis of Fluid Flow
Nov. 11 – Nov. 16 Chapter 7 Dimensional Analysis, Similitude, and Modeling
Nov. 18 – Nov. 25 Chapter 8 Viscous Flow in Pipes
Nov. 30 Chapter 9 Flow Over Immersed Bodies
Dec. 2 Final Review
TBA Final Exam
What is Fluid Mechanics?
� It is an applied mechanics, which studies liquids and
gases at rest or in motion
Examples of applied areas:
� Canal, levee, and dam systems;
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� Pumps, compressors, and piping and ducting systems;
� Aerodynamics for automobiles and airplanes;
� Development of flow measurement devices such as gas
pump meters.
*Pictures courtesy from Google
More Examples
� Renewable Energy:
Wind Power
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KiteGen (Pritchard, 2011) Sky Windpower (Pritchard, 2011)
� First, let’s look at shear stress in mechanics:
What are fluids?
14*picture courtesy from whatsontheare.com
What are fluids? (cont’d)
� Compared with solids, a fluid is a substance that
deforms continuously under the application of a shear
(tangential) stress no matter how small the shear
stress may be.
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Remarks:
� Some exceptions of the above definition
(tar, toothpaste)
� The definition is for Continuum, average properties as
compared to discrete molecules
Basic Dimensions
� Primary/basic quantities/dimensions
M: mass
L: length
T: time
Θ: temperature
F: force
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F: force
� Two Basic Dimension Systems:
MLT: mass length time
FLT: force length time
Secondary Dimensions
� Secondary/derived quantities/dimensions
Examples:
area, velocity, density ρ, acceleration etc.
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� All secondary dimensions can be derived from basic
dimensions in either FLT or MLT systems.
FLT and MLT Systems
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System of Units
� Systems of units
� SI (International System)
meter (m), second (s), kilogram (kg), kelvin (K), newton
(N), joule (J) for work, watt (W) for power
Sometimes, combined, kW means killowatts
K = °C + 273.15
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K = °C + 273.15
� BG (British Gravitational System)
� EE (English Engineering System)
Dimension Homogeneity
� Dimension Homogeneity is dimensional consistency
for an engineering equation
1. Each term should have the same dimension
2. The dimension of the left hand side is the same as
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that of the right hand side of the equation
Example: for the equation, Z1 and Z2 are length, V1
and V2 are velocity, P1 and P2 are pressure, find γ1
and γ2 ‘s dimension
2
2
2
2
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2
1
1
1
22z
g
Vpz
g
Vp++=++
γγ
An Example of Dimension
Homogeneity
� If V is a velocity, determine the dimensions of Z, α,
and G, which appear in the dimensionally
homogeneous equation:
Dimensions might be used
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GZV +−= )1(αDimensions might be used
V (velocity) LT-1
Force or Weight F
Length L
Force or Weight F
p (pressure) FL-2
ρ (density) FL-4T2
γ (specific weight) FL-3
Common Properties:
Fluid Mass and Weight� Density (kg/m3) – ρ – [Rho]
� Specific volume (m3/kg) – ν – [Upsilon]
� Specific weight (N/m3) – γ = ρg – [Gamma]
� Specific gravity – SG = ρfluid/ρwater
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Density of Water
Basic Equations
� Basic laws governing any fluid motion or at rest
1. The conservation of mass
2. Newton’s second law of motion
3. The principle of angular momentum
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3. The principle of angular momentum
4. The first law of thermodynamics
5. The second law of thermodynamics
Ideal (Perfect) Gas Law
� Equation of state for an ideal gas
RT
p=ρ
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� Pressure – p
� Unit: N/m2, pascal (Pa)
� Absolute Pressure and Gage Pressure
� Standard sea-level atmospheric pressure 101.33
kPa(abs) or 14.696 psi(abs) – pound per square inch
� Specific gas constant R = Ru/M
� Universal gas constant Ru = 8.314 J/K�mol
An Example of 1st Law Application
� A piston-cylinder device contains
0.95 kg of oxygen (O2).
Initially, T1 = 27°C, P1 = 150 kPa (abs)
Then, heat is added, so
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Then, heat is added, so
At the end, T2 = 627°C.
Determine the heat added to the system.
