This session will be recorded.
MMAN2700: Thermodynamics
Dr Irene Renaud-Assemat
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Please type any questions in the chat, I will answer them during the
Q&A sessions
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Prepare a pen, paper and a calculator
We will start at 5 past the hour to give everyone time to arrive.
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Thermodynamics MMAN2700
Irene Renaud-Assemat
i.renaudassemat@unsw.edu.au
Room 208C Ainsworth Building J17
Who am I?
MSc in
Mechanical
Engineering
2005
Teaching
associate
2006-2011
PhD in Fluid
Dynamics
2011
Teacher in High
School
2011-2014
Lecturer in
Mechanical
Engineering
2014 - 2020
Senior Lecturer
Mechanical
Engineering
2020-present
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TODAY
How the topic will be delivered
What is Thermodynamics
Early engines
A problem solving template
Topic 1: Systems and Energy / Heat and Work
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https://PollEv.com/irenerenauda439
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Course organisation
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Intended learning outcomes
At the end of this course, you should be able to:

Demonstrate knowledge of key concepts of thermodynamics

Apply the 1st and 2nd law of thermodynamics to solve steady-state problems on
closed and open systems, and to analyse the behaviour of cycles

Carry out, on working machinery, measurements of thermodynamic and
mechanical properties, and identify links between theoretical analysis methods
and actual performance
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Demonstrators
Zhao Sha
Tracey Nguyen
Mohamed Mahmoud
Ryan Zi Seng Chuah
Justin Chuwardi
Mobarak Hossain
Guang Li
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Course contents
Topic 1: Systems and Energy
• Heat and Work
• 1st law in closed systems
• Internal energy
Topic 4: 1st law in open systems
• Steady flow
• Applications
Topic 5: 2nd law of
thermodynamics
• Entropy
• Applications
Revisions
Topic 2: Energy balances
Laboratories
•
•
•
•
• Thermoboards
• Compressor rig
Ideal gases
Enthalpy
Moving boundary work
Isentropic and polytropic processes
Topic 3: Properties of pure substances
Timetable – Teaching activities
Week 1
Wed 12-2pm; Thu 12-2pm
Lectures: Topic 1
Week 2
Lectures: Topic 2
Example class
Week 3
Lectures: Topic 2
Example class
Quiz 1 (10%)
Week 4
Lectures: Topic 3
Example class
Lab 1
Week 5
Lectures: Topic 3
Example class
Quiz 2 (10%)
Week 6
Guest Lecture (Friday 24/03 2-4pm)
Example class
Week 7
Lectures: Topic 4
Example class
Mid-term quiz (30%)
Quiz 3 (10%)
Week 8
Lectures: Topic 5
Example class
Lab 2
Week 9
Lectures: Topic 5
Example class
Week 10
Lectures: Revisions
Example class
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How the unit runs
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Assessment
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Support
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Laboratories – 2 x 15%
3 Quizzes (Wednesday in weeks 3, 5 and 7 at 6pm) – 3 x 10%
Final exam – 40%
Email: i.renaudassemat@unsw.edu.au
Demonstrators
Textbooks
G.F.C Rogers & Y. Mayhew, Thermodynamics and Transport properties of fluids, SI units, 5th
edition, Blackwell publishing
 Y.A. Cengel, M.A. Boles & M. Kanoglu, Thermodynamics: An engineering approach, 9th edition in SI
units, McGraw Hill education

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Course communication
Microsoft Teams
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For communication: Please check Teams regularly for any important
announcements
Post your questions in the relevant channel. Expect a response within one
business day
Teaching material is uploaded on Moodle
For assessment
You can contact me by email, I will do my best to reply within one business14day
Q&A
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What is thermodynamics?
“the branch of physics that is
concerned with the relationship
between heat and other forms of
energy”
Collins Dictionary (online)
Thermo dynamics
Heat
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Work / movement
Early engines
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The problem
This Photo by Unknown Author is licensed under CC BY-NC-ND
This Photo by Unknown Author is licensed under CC BY-SA
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Evolution of steam engines – the industrial
revolution
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Savery mine pump, late 17th century
+
No moving parts
-
Machining limitations so only worked to ~10m
depth
-
Needed to cool cylinder – intermittent working
-
wasted energy in re-heating cylinder each cycle
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Egg experiment
https://www.youtube.com/watch?v=6R215vLf29w
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Newcomen atmospheric engine, early 18th
century
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Injected water to cool steam

Could replace 500 horses

+ not limited by depth as it drove an old-style
pump in the mine

- still wasted energy re-heating the cylinder after
injection of cold water each cycle
http://www.animatedengines.com/newcomen.html
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Watt steam engine, late 18th
century

Separate condenser from boiler

>3 times more efficient
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The principles (Flanders & Swann Lyrics)
“The 1st law of thermodynamics
Heat is work and work is
heat…”
“The second law of
thermodynamics
Heat cannot of itself pass from
one body to a hotter body”
http://www.youtube.com/watch?v=VnbiVw_1FNs&t=2m7s
Thermodynamics:
heat and work
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First and Second Law by an old comedy duo,
Flanders and Swann
The first law of thermodynamics:
Heat is work and work is heat.
Heat is work and work is heat.
Very good. The second law of thermodynamics:
Heat cannot of itself pass from one body to a hotter body.
Heat cannot of itself pass from one body to a hotter body.
Heat won't pass from a cooler to a hotter.
Heat won't pass from a cooler to a hotter.
You can try it if you like but you far better not-er!
You can try it if you like but you far better not-er!
'Cause the cold in the cooler will get hotter as a rule-r,
'Cause the cold in the cooler will get hotter as a rule-r,
Because the hotter body's heat will pass to the cooler
'Cause the hotter body's heat will pass to the cooler
First Law:
Heat is work and work is heat and work is heat and heat is work.
Heat will pass by conduction.
Heat will pass by conduction.
Heat will pass by convection.
Heat will pass by convection.
Heat will pass by radiation.
Heat will pass by radiation.
And that's a physical law!
Heat is work, and work's a curse
And all the heat in the universe
Is gonna cool down
'Cause it can't increase
Then there'll be no more work
And there'll be perfect peace
Really?
Yeah, that's entropy, man!
And all because of the second law of thermodynamics, which lays down:
That you can't pass heat from a cooler to a hotter
Try it if you like but you far better not-er
'Cause the cold in the cooler will get hotter as a rule-r
'Cause the hotter body's heat will pass to the cooler
Oh, you can't pass heat from the cooler to the hotter
You can try it if you like but you'll only look a fool-er
'Cause the cold in the cooler will get hotter as a ruler
And that's a physical law...
Oh, I'm hot!
Hot? That's because you've been working!
Oh, Beatles nothing!
And that's the first and second law of thermodynamics!
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A problem solving template
1.
State the problem
2.
Draw a relevant diagram and label it
3.
Write down any assumptions
4.
Write down any physical laws or
equations
5.
Write down any properties
6.
Do the calculation
7.
Discuss the answer
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A problem solving template
1.
State the problem
2.
Draw a relevant diagram and label it
3.
Write down any assumptions
4.
Write down any physical laws or
equations
5.
Write down any properties
6.
Do the calculation
7.
Discuss the answer
A cylindrical vessel has a diameter of 2 inches
and a length of 2m. If it is filled with water
(density 1g/cm3) calculate the mass of liquid
in the vessel.
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A problem solving template
1.
State the problem
2.
Draw a relevant diagram and label it
3.
Write down any assumptions
4.
Write down any physical laws or equations
5.
Write down any properties
6.
Do the calculation
7.
Discuss the answer
A cylindrical vessel has a diameter of 2 inches
and a length of 2m. If it is filled with water
(density 1g/cm3) calculate the mass of liquid
in the vessel.
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Q&A
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Topic 1: Systems and Energy
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Contents

System and its properties
(definitions)
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Work and Heat
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Systems and its properties
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System and boundaries
System:
“a set of connected things or
devices that operate together”
Cambridge Dictionary (online)
Surroundings
System
System boundary
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Open and closed
Closed
No transfer of
material
between system
and
surroundings
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Open
Material can be
transferred
between system
and
surroundings
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Systems - examples
Closed system with a moving
boundary
Closed system – control mass
Isolated system
Open system – control volume
E.g. compressors, pumps, turbines, heat
exchangers…
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Properties of a system
6 state properties:
 Temperature, T
 Pressure, p
 Density, 𝜌𝜌 (or specific volume v)
 Internal energy, u
Non-capital letters mean ‘per unit mass’, or ‘specific’
 Enthalpy, h
E.g. specific volume (𝑚𝑚3 /𝑘𝑘𝑘𝑘) = 1/density
 Entropy, s
“A quantity is a property if its change in value between 2 states
is independent of the process” (Moran & Shapiro, 2008)
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Pressure
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Force per unit area – SI unit: N/m2 (or Pa)
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Other units: bar, psi, mmHg…
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Isotropic – equal in all directions
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Gauge pressure vs absolute pressure
𝑃𝑃𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔 = 𝑃𝑃𝑎𝑎𝑎𝑎𝑎𝑎 − 𝑃𝑃𝑎𝑎𝑎𝑎𝑎𝑎
𝑃𝑃𝑎𝑎𝑎𝑎𝑎𝑎 = 𝑃𝑃𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔 + 𝑃𝑃𝑎𝑎𝑎𝑎𝑎𝑎
Isotropic
𝑃𝑃𝑎𝑎𝑎𝑎𝑎𝑎 = 𝜌𝜌𝐻𝐻𝐻𝐻 𝑔𝑔𝑔
where 𝜌𝜌𝐻𝐻𝐻𝐻 is the density of
mercury, g is the local
gravitational acceleration and h
is the height of the mercury
column above the free surface
barometer
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Negative
pressure??
Absolute: p=0 → vacuum
Standard atmospheric pressure: 1atm = 1.013bar
1 bar = 105 Pa
Barometer
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Temperature
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Temperature scales:
Celsius, Fahrenheit scales depend on material and 2 datum points
 Thermodynamic temperature scale: Kelvin (no dependence on
particular substance)
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𝑇𝑇 𝐾𝐾 = 𝑇𝑇 °𝐶𝐶 + 273.15
Thermal equilibrium
0th law
“If 2 bodies are in thermal equilibrium with a 3rd body, they are also
in thermal equilibrium with each other”
or
“2 bodies at the same temperature are at thermal equilibrium”’
Freezing point
of water
Boiling point of
water
A
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C
B
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Equilibrium and the state postulate
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Equilibrium: a system is in a state of
equilibrium (or balance) if no changes occur in
any of the macroscopic properties of the
system
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State postulate: 2 independent intensive
properties are required to specify the state of
a system
 e.g.
 e.g.
{p,T} → {ρ, 𝑢𝑢, ℎ, 𝑠𝑠}
ideal gas law 𝑝𝑝𝑝𝑝 = 𝑚𝑚𝑚𝑚𝑚𝑚
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Intensive vs extensive
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Extensive depends on system size,
i.e. extent of the system
m
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(kg), V (m3), U (kJ), H (kJ), S (kJ/K)
Intensive is independent of system
size
T
(K), p (kN/m2), v (m3/kg)
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
Can transform extensive to
intensive:
𝑉𝑉 1 𝑚𝑚3
v= =
𝑚𝑚 𝜌𝜌 𝑘𝑘𝑘𝑘
𝑈𝑈 𝑘𝑘𝑘𝑘
𝑢𝑢 =
𝑚𝑚 𝑘𝑘𝑘𝑘
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Process
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Equilibrium: all forces balanced and
temperatures equal
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Process: changes system from one
equilibrium state to another
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Path: can be plotted on process diagram
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Quasi-equilibrium process: very close to
equilibrium along the path
Infinitesimally small driving force
or temperature difference
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Q&A
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Start problem sheet 1: Systems and Energy
You should be able to answer the foundation questions
and standard questions up to question 8.
What to do
next
Write up your notes
Next lecture tomorrow at 12pm
Heat and Work
1st law of thermodynamics in closed systems
Post your questions on Teams in the specific channel
AENG10003: Engineering Science 1: Thermofluids
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Q&A
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