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Faculty of Engineering
Mechanical Engineering Dept.
Dr. Emad M. Saad Mechanical Engineering Dept.
Faculty of Engineering
Fayoum University
Entropy
Lecture (1)
on
By
2015 - 2016
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Lecture (1) – Thermodynamics – 2nd year
Course Syllabus
Text Books: Lectures notes
References: Y. A. Çengel and M. Boles, Thermodynamics: An Engineering
Approach, 5th ed., McGraw Hill, 2007.
Evaluation: 1. Homework, attendance and assignments; equivalent 20%.
2. Mid exam; equivalent 20%.
3. Final exam; equivalent 60%.
Professor: Facebook: DrEmad Elasid
Website: http://www.fayoum.edu.eg/emad
Email: emadsaad@fayoum.edu.eg
Office Hours: Monday: 9:00 - 14:30
or by Appointment
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Course Syllabus
1. Entropy: definition, change in entropy in reversible process, entropy and irreversibility,
principle of increase in entropy, relation of entropy with the properties.
2. Availability and irreversibility: entropy balance, available energy, reversible work, availability
analysis, exergy destruction, second law efficiency.
3. The pure substance: phase equilibrium, p-v-T diagrams, property tables and charts.
4. Gas and power cycle: Ideal gas cycles: Otto, Diesel, Dual, Brayton
5. Vapor cycles: Rankine cycle – modification to Rankine cycle.
6. Refrigeration cycles: reversed Carnot cycle, vapor compression cycles, vapor absorption cycles.
7. Gas mixtures: Mixture of ideal gas and vapor, Dalton law of additive pressure, Amagat’s law
of additive volumes.
8. Thermodynamics of reactant systems: chemical equilibrium, combustion, enthalpy of
formation, enthalpy of reaction, adiabatic flame temperature.
Lecture (1) – Thermodynamics – 2nd year
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Lecture (1) –Thermodynamics – 2nd year
Entropy is a measure of the amount of
disorder in a system. The more disorder, the
higher the entropy of the system.
Entropy in thermodynamics
Entropy is a measure of the number of specific ways in which
a thermodynamic system may be arranged
Entropy concept in Life
Entropy is a measure of the theoretical amount of energy
that can not convert to mechanical work in thermodynamic
system
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Lecture (1) –Thermodynamics – 2nd year
Entropy is a function of a quantity of heat which shows the possibility of conversion of that heat into work. The increase in entropy is small when heat is added at a high temperature and is greater when heat addition is made at a lower temperature. Thus for maximum entropy, there is minimum availability for conversion into work and for minimum entropy there is maximum availability for conversion into work.
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Lecture (1) –Thermodynamics – 2nd year
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An important inequality that has major consequences in
thermodynamics is the Clausius inequality and is expressed as:
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Lecture (1) –Thermodynamics – 2nd year
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Nozzle Compressor & pump
Turbine
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