1) The document discusses key concepts in thermodynamics including the limitations of the first law, heat engines, heat pumps, and parameters of performance like coefficient of performance. 2) It also covers the second law of thermodynamics including Kelvin-Planck and Clausius statements, perpetual motion machines, and the equivalence of the statements. 3) Additionally, it discusses Carnot's principle and cycle, the thermodynamic temperature scale, and an elementary treatment of the third law of thermodynamics.

1. T H E R M O D Y N A M I C S
BY
C H . S R AVA N T H I
A S S I S TA N T P R O C E S S O R
M E C H A N I C A L E N G I N E E R I N G
D E P A R T M E N T
J B I E T

2. UNIT 2
Lesson 1: (2 periods)
•Limitations of the First Law
•Thermal Reservoir
•Heat Engine
•Heat pump
•Parameters of performance

3. LIMITATIONS OF THE FIRST LAW
• Feasibility of a process
can the rod at lower temperature will get hot by it’s own
• Direction of flow of energy
Higher temperature to lower Temperature
Or
Lower temperature to higher temperature

5. THERMAL RESERVOIR

6. HEAT ENGINE

8. HEAT PUMP

9. REFRIGERATOR

10. PARAMETERS OF PERFORMANCE
• Coefficient of performance

11. Lesson 2 : (2 periods)
•Second Law of Thermodynamics,
•Kelvin-Planck and Clausius Statements and their
Equivalence / Corollaries,
•PMM of Second kind

12. KELVIN – PLANCK STATEMENT OF
SECOND LAW
•It is impossible for a heat engine to
produce net work in a complete cycle if
it exchanges heat only with bodies at a
single fixed temperature.

13. CLAUSIUS STATEMENT OF SECOND
LAW
•It is impossible to construct a device which
operating in a cycle will produce no effect
other than the transfer of heat from cooler
to a hotter body.

14. PERPETUAL MOTION MACHINE OF
SECOND KIND - PMM2
•If the heat engine produces net work in a
complete cycle by exchanging heat with only
one reservoir, thus violating Kelvin – Plank
statement. Such a heat engine is called
perpetual motion machine of second kind,
abbreviated to PMM2.

16. EQUIVALENCE OF KELVIN – PLANCK
AND CLAUSIUS STATEMENT

18. Lesson 3 : (2 periods)
• Carnot’s principle
• Carnot cycle and its specialties
• Thermodynamic scale of Temperature
• Elementary Treatment of the Third Law of
Thermodynamics

19. CARNOT CYCLE AND ITS SPECIALTIES
•A reversible cycle is an ideal hypothetical
cycle in which all the processes constituting
the cycle are reversible.
• Carnot cycle is a reversible cycle.

22. REVERSED CARNOT HEAT ENGINE

23. CARNOT’S PRINCIPLE
•It states that of all heat engines operating
between a given constant temperature
source and a given constant temperature
sink, none has a higher efficiency than a
reversible engine.

26. COROLLARY OF CARNOT’S PRINCIPLE
•Efficiency of all reversible heat engines
operating between same temperature levels is
the same.
•The efficiency of a reversible engine is
independent of the nature of nature or amount
of the working substance undergoing the cycle.

27. ABSOLUTE THERMODYNAMIC SCALE OF
TEMPERATURE

32. ELEMENTARY TREATMENT OF THE
THIRD LAW OF THERMODYNAMICS
•It is impossible by any procedure, no
matter how idealised, to reduce any system
to absolute zero of temperature in a finite
number of operations.

33. EFFICIENCY OF A REVERSIBLE HEAT
ENGINE

35. ASSIGNMENT QUESTIONS FROM LESSON 1,2,3 OF UNIT 2

37. Lesson 4 : (4 periods)
•Entropy
•Clausius Inequality
•Principle of Entropy Increase or Entropy
Principle

38. TWO REVERSIBLE ADIABATIC PATHS
CAN NOT INTERSECT EACH OTHER
• Reversible processes AB, BC,
CA
• AC, BC reversible adiabatics
• AB reversible isotherm
• Reversible cycle ABCA
• Impossible cycle
• Exchanging heat with single
thermal reservoir
• Violation of kelvin planck
statement
• Two constant property lines
can never intersect

39. CLAUSIUS’ THEORM
• Reversible path i-f
• Reversible adiabatics i-
a, b-f
• Reversible isotherm a-
b
• Area i-a-b-f = Area i-f
• Reversible path =
adiabatIc + isotherm +
adiabatIc
• Heat transferred in
isothermal process a-b
= Heat transferred in
original path i-f

41. • Reversible cycle
• Divided in to large number of srtips by adiabatics
• Each strip is Closed at tip and bottom by reversible isotherm
• Heat transfer through all the isothermal = Heat transfer
through original cycle
• Original cycle is replaced with large number of carnot cycles
• The cyclic integral of dQ/T for a reversible cycle is equal to
zero. This is known as clausius theorm.

43. THE PROPERTY OF ENTROPY

45. TEMPERATURE ENTROPY PLOT

48. CLAUSIUS INEQUALITY

51. ENTROPY
CHANGE IN AN
IRREVERSIBLE
PROCESS

53. ENTROPY PRINCIPLE
• Entropy of an isolated system can never decrease
• It always increases and remains constant only when process is
reversible
• This is known as Principle of increase of entropy or the entropy
principle
• The energy of the world (universe) is constant
• The entropy of the world tends towards maximum
• The entropy increase of an isolated system is a measure of the
extent of irreversibility of the process undergone by the system.
• The entropy of an isolated system always increases and becomes a
maximum at the state of equilibrium

55. APPLICATIONS OF ENTROPY
PRINCIPLE
• Transfer of Heat through a Finite Temperature Difference
• Mixing of Two Fluids
• Maximum Work Obtainable from Two Finite Bodies at Temperatures T1
and T2
• Maximum Work Obtainable from a Finite Body and a TER
• Processes Exhibiting External Mechanical Irreversibility
a) Isothermal Dissipation of Work
b)Adiabatic Dissipation of Work

56. TRANSFER OF HEAT THROUGH A
FINITE TEMPERATURE DIFFERENCE

57. • If T1 > T2, The process is irreversible and possible.
• If T1 = T2, The process is reversible.
• If T1 < T2, The process is impossible.

58. MIXING OF TWO FLUIDS

61. MAXIMUM WORK OBTAINABLE FROM
TWO FINITE BODIES AT TEMPERATURES
T1 AND T2
• The working fluid
operating in the
heat engine cycle
does not undergo
any entropy change.

63. MAXIMUM WORK OBTAINABLE FROM
A FINITE BODY AND A TER

64. PROCESSES EXHIBITING EXTERNAL
MECHANICAL IRREVERSIBILITY
a) Isothermal Dissipation of Work

65. • b)Adiabatic Dissipation of Work

67. ENTROPY TRANSFER WITH HEAT
FLOW
• There is entropy
transfer from the
system to
surroundings along
with heat flow
• Flow of disorder along
with heat

68. • No entropy
transfer
associated
with work

69. ENTROPY GENERATION IN A CLOSED
SYSTEM
• By heat
interaction in
which there
is entropy
transfer
• By internal
irreversibility
or dissipative
effects in
which work
or K.E is
dissipated
into internal
energy
increase

72. ENTROPY GENERATION IN AN OPEN
SYSTEM

75. FIRST AND SECOND LAWS COMBINED

76. REVERSIBLE
ADIABATIC
WORK IN A
STEADY FLOW
SYSTEM

78. ENTROPY AND DIRECTION: THE SECOND
LAW - A
DIRECTIONAL LAW OF NATURE
•A process always occurs in such
a direction as to cause an
increase in the entropy of
universe.

79. ENTROPY AND DISORDER
• The entropy of a system is a
measure of the degree of
molecular disorder editing in
system.

80. ABSOLUTE ENTROPY
•Always entropy change is calculate.
•If absolute entropy value is
required, then assign zero value to
entropy at an arbitrarily chiken
stardard state.

81. POSTULATORY THERMODYNAMICS
•Postulate I - Defines the equilibrium state
•Postulate II - Introduces the property entropy
which renders maximum at the final
equilibrium state
•Postulate III - Refers to additive nature of
entropy
•Postulate IV - Mentions that the entropy of any
system vanishes at the absolute zero of

82. ASSIGNMENT QUESTIONS FROM LESSON 4 OF UNIT 2

86. LESSON 5 : (4 PERIODS)
•Energy Equation
•Availability and Irreversibility
•Thermodynamic Potentials
•Gibbs and Helmholtz Functions
•Maxwell Relations

87. AVAILABLE ENERGY
•According to second law of thermodynamics
low grade energy can not be completely
converted into high grade energy.
•Part of low grade energy which is available for
conversion is known as available energy.
•Part of available energy which must be rejected
is called unavailable energy.

88. AVAILABLE ENERGY REFERRED TO A
CYCLE
• Maximum workoutput obtainable from a certain heat
input in a cyclic heat engine is called the available
energy (A.E) or exergy
• Minimum energy that has to be rejected to the sink by
second law of thermodynamics is called the
unavailable energy (U. E) or anergy

92. DECREASE IN
AVAILABLE
ENERGY WHEN
HEAT IS
TRANSFERRED
THROUGH A
FINITE
TEMPERATURE
DIFFERENCE

95. AVAILABLE ENERGY FROM A FINITE
ENERGY SOURCE

97. QUALITY OF ENERGY

98. • Heat loss of 1 kJ, at, say, 1000° C is
more harmful than the same heat
loss of 1kJ at, say, 100° C

99. • Available energy or exergy of fluid at a higher temperature T1
is more than that at a lower temperature T2, and decrease as
the temperature decreases.

100. LAW OF DEGRADATION OF ENERGY
•First law states that energy is conserved
quantitywise. It is also called as law of
conservation of energy.
•The second law emphasizes that energy always
degrades qualitywise. It is also called as law of
degradation of energy.
•Energy is always conserved but it’s quality is
always degraded.

101. MAXIMUM WORK IN A REVERSIBLE
PROCESS

103. WORK DONE IN ALL REVERSIBLE
PROCESSES IS THE SAME
• Two reversible processes must
coincide and produce equal amount
of work
• There will be only one reversible path
between two end states

104. REVERSIBL
E WORK BY
AN OPEN
SYSTEM
EXCHANGIN
G
HEAT ONLY
WITH THE
SURROUND
INGS
• For
maximum
work the
process must
be entirely
reversible

107. REVERSI
BLE
WORK IN
A
STEADY
FLOW
PROCESS

109. REVERS
IBLE
WORK
IN A
CLOSED
SYSTE
M

110. USEFUL WORK
•The useful work is defined as the actual work
delivered by the system less the work
performed on the atmosphere
•All of the work W of the system would not
available for delivery, since a certain portion of
it would be spent in pushing out the
atmosphere.

114. MAXIMUM
USEFUL WORK
OBTAINABLE
WHEN THE
SYSTEM
EXCHANGES
HEAT WITH A
THERMAL
RESERVOIR IN
ADDITION TO
THE
ATMOSPHERE

115. DEAD STATE

116. AVAILABILITY
•The availability (A) of a given system is
defined as the maximum useful work
obtainable in process in which the system
comes to equilibrium with its surroundings.

117. AVAILABILITY IN A STEADY FLOW
PROCESS

119. AVAILABILITY IN A NONFLOW PROCESS

120. AVAILABILITY IN CHEMICAL
REACTIONS

122. IRREVERS
IBILITY
AND
GOUY-
STODOLA
THEOREM

123. APPLICATION OF GOUY-STODOLA
EQUATION
(a) Heat Transfer through a Finite
Temperature Difference
(b) Flow with Friction
(c) Mixing of Two Fluids

124. SECOND
LAW
EFFICIEN
CY