Transcript outline - Concordia University

Course Outline
Combustion
MECH 6191
Department of Mechanical and Industrial Engineering
Concordia University
Instructor: Dr. Hoi Dick Ng
Room: EV 004.229
Tel: (514) 848-2424 ext 3177
E-mail: [email protected]
Office Hours: Mondays 1:30pm - 3:00pm or by appointment
Webpage:
http://users.encs.concordia.ca/~hoing/Teaching/mech6191/mech6191.html
• Contain class lecture powerpoints & supplements
• Homework exercises
• Last minute announcements
Motivation
Combustion  What is this course all about?
What is combustion???
What is combustion?
Combustion: the study of chemical reactions between fuel and
oxidizer molecules resulting in the increase in the internal (thermal)
energy of the products from the difference between the chemical
bond energies of the reactant and product species
CH4 + 2O2 -> CO2 + 2H2O + HR
to convert the large amount of thermal energy that is released in the
chemical reactions to mechanical work via heat engines (power plants).
Understand the fundamental processes during chemical reactions
Study the coupling between the heat release and thermo-fluid dynamics
Historical perspectives
Discovery of FIRE …. Long long time ago….
The use of combustion in technology dates back to:
100 A.D. (the development of metallurgy)
1000-1200 A.D. (pyrotechnic rockets and furnaces)
1300 A.D. (guns)
1600 A.D. (steam engine)
Experimental scientific studies of combustion
began about 1660 in the Oxford School of
Chemistry by Robert Boyle and Robert Hooke
Historical perspectives
First modern definition of combustion in 1665
Against the ancient ideas that FIRE was one of
the 4 basic elements
An exerpt from Hooke in 1665: “…it seems
resonable to think that there is no such thing as an
Element of Fire…but that that shinning transient
body which we call Flame, is nothing else but a
mixture of Air, and volatile sulphureous parts of
dissoluble or combustion bodies, which are acting
upon each other whil’st they ascent.”
Historical perspectives
Refined definition of combustion by Antoine Lavoisier and later
on by Claude L. Berthollet and John Dalton:
interpreted combustion in terms of a form of oxidation
Chemistry consideration
In the late 1800’s, Otto and Diesel engines were developed
Another mode of combustion, the phenomenon of detonations,
was discovered by Bunsen, Mallard and LeChatelier (also
independently by Berthelot and Vielle).
The foundation of the modern Science of Combustion
The basis for much of our understanding of combustion was
developed in the middle of the century (1940’s), particularly by
Zel’dovich, Schelkin, Frank-Kamenetskii and others.
Motivation
Why do we need to study combustion?
Combustion has a great economic, social and technical importance
Energy/power production (almost 90% of world energy
still comes from combustion process)
Environmental problems
- pollution problem
- global warming
WHERE THE WORLD GETS ITS ENERGY?
• Still Heavily rely on a
Fossil-fuel based
combustion system
Supply and Demand
Projections of world energy production into the 21st century
• There is no denying that our fossil fuel supplies are dwindling; yet, our
dependence upon them is as great as ever
Combustion technology
Tackle the problem from the demand side of the equation
• Design automobile, jet engine, etc with better
efficiency to reduce the fuel consumption
Develop new fossil technologies
• New resources?
 Require knowledge in combustion
Motivation
Why do we need to study combustion?
Combustion has a great economic, social and technical importance
Energy/power production (almost 90% of world energy
still comes from combustion process)
Environmental problems
- pollution problem
- global warming
Sky view in Shanghai
Environmental problems
• Greenhouse gases emissions: Global warming
Climate change
• Damage from storms,
floods, wildfires
• Property losses from
sea-level rise
• Productivity of farms,
forests, & fisheries
• Livability of cities in
summer
• Geography of disease
1750,
the beginning
of the
industrial
revolution
ENVIRONMENTAL PROBLEM
The projected carbon emission
in the next 30 years we will add
3x more CO2 emission than the
previous 250 years!
The possibility of global
warming and serious
climate change
Figure. The likely increases in CO2
concentration over the next century
corresponding to four of the IPCC
emission scenarios.
2 x CO2
Computer simulations
by the Princeton
Geophysical Fluid
Dynamics Lab for CO2
increases above preindustrial revolution
levels:
2x CO2 : 5 – 8° F
4 x CO2
4x CO2 : 15-25° F
Pre-industrial:
~275 ppm
Today:
~380 ppm
Combustion Research
Combustion is a fascinating multi-disciplinary science
Kinetics theory
Computer simulations
Thermodynamics
Combustion
Applied math
(Asymptotic methods)
Heat transfer
Diagnostics &
measurement
Fluid mechanics
Transport processes
Prerequisites
Thermodynamics I and II (Mech 341,351)
Strong background in:
• Thermodynamics: thorough understanding of different
thermodynamics properties/relationship and laws
of thermodynamics
• Basic fluid dynamics concepts
• Knowledge of calculus and numerical methods
Course topics
Combustion is a very broad topic:
What are we going to study in this course?
Course topics
Basic questions:
How much energy is released in a chemical reaction?
When does a reaction reach equilibrium?
How fast do reactions occur?
How does a flame propagate?
How does a flame become unstable and turbulent?
How does a detonation propagate?
What combustion parameters are important for industrial safety consideration?
How does the combustion of gases, liquids and solids differ?
Course topics
Specifically, we will look into more details the following topics of
combustion:
Chemical thermodynamics
Chemical kinetics
conservation equations for multi-component reacting systems
Premixed laminar flame theory
Gaseous detonations
Gaseous diffusion flames
Combustion instability mechanisms
Industrial safety considerations
Droplet combustion
References
• K.K. Kuo (2005) Principles of Combustion, 2nd ed. John Wiley & Sons
• Notes and assigned reading materials will be posted in the website
• Additional references:
I. Glassman (1996) Combustion, 3rd ed. Academic Press
S.R. Turns (1996) An Introduction to Combustion, 2nd ed. McGraw Hill B.
Lewis & von Elbe (1987) Combustion, Flame and Explosion of Gases, 3rd ed.
Academic Press
F. Williams (1985) Combustion Theory, Benjamin & Cummings
C.K. Law (2005) Combustion Physics, Cambridge University Press
• Write your own notebook
Concordia University
Evaluation scheme
Midterm quiz
Final quiz (closed book)
Project
- proposal/audit
- report
- presentation
Concordia University
25%
45%
5%
20%
5%
How to succeed in this course
• Review your basic engineering subjects
(e.g. thermodynamics, fluid mechanics, heat transfer)
• Study class lectures, read the textbook and update your
notebook regularly
• Do the homework
• Read literature on combustion and develop an interest in
the subject. Try to write the main points down in your
notebook (keep a good learning record)
• Discuss and collaborate with your colleagues
Most important, ENJOY this course
Concordia University
Quad Chart
Source: http://www.canis.uiuc.edu/
Concordia University