Subject: ME8391 Engineering Thermodynamics
Topic: Basic Concepts & First law of Thermodynamics
B.E. Mechanical Engineering
Second year, III Semester.
[Anna University R-2017]
this is my presentation about 2nd law of thermodynamic. this is part of engineering thermodynamic in mechanical engineering. here discussed about heat transfer, heat engines, thermal efficiency of heat pumps and refrigerator and its equation for perfect work done with best figure and table wise discription, entropy and change in entropy, isentropic process for turbines and compressor and many more.
i hope, it will helpful to the students and peoples in the search of topics mentioned
it is informative to study to even get passing marks or for revision
this is my presentation about 2nd law of thermodynamic. this is part of engineering thermodynamic in mechanical engineering. here discussed about heat transfer, heat engines, thermal efficiency of heat pumps and refrigerator and its equation for perfect work done with best figure and table wise discription, entropy and change in entropy, isentropic process for turbines and compressor and many more.
i hope, it will helpful to the students and peoples in the search of topics mentioned
it is informative to study to even get passing marks or for revision
In this PPT have have covered
1. Basic thermodynamics definition
2. Thermodynamics law
3. Properties , cycle, Process
4. Derivation of the Process
5.Formula for the numericals.
This topic is use full for those students who want to study basic thermodynamics as a part of their University syllabus.
Most of the university having basic Mechanical engineering as a subject and in this subject Thermodynamics is a topic so by this PPT our aim is to give presentable knowledge of the subject
MICROSCOPIC & MACROSCOPIC POINT OF VIEW , THERMODYNAMIC SYSTEM & CONTROL VO...KRUNAL RAVAL
Thermodynamics is science of energy transfer and its effects on properties.
Main aim is to convert disorganized form of energy into organized form of energy in an efficient manner. Based on the macroscopic approach which does not require knowledge of behavior of individual particles and is called classical thermodynamics.
To download this lecture notes kindly visit website or contact me
Topics include: visit my website (www.mech-4u.weebly.com)
1) introduction to thermodynamics
2) basics concepts of thermodynamics
3) types of system
4) properties of system
5) zeroth law of thermodynamics
6) concept of heat and work
7) properties of steam
8) properties of ideal gas
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In this PPT have have covered
1. Basic thermodynamics definition
2. Thermodynamics law
3. Properties , cycle, Process
4. Derivation of the Process
5.Formula for the numericals.
This topic is use full for those students who want to study basic thermodynamics as a part of their University syllabus.
Most of the university having basic Mechanical engineering as a subject and in this subject Thermodynamics is a topic so by this PPT our aim is to give presentable knowledge of the subject
MICROSCOPIC & MACROSCOPIC POINT OF VIEW , THERMODYNAMIC SYSTEM & CONTROL VO...KRUNAL RAVAL
Thermodynamics is science of energy transfer and its effects on properties.
Main aim is to convert disorganized form of energy into organized form of energy in an efficient manner. Based on the macroscopic approach which does not require knowledge of behavior of individual particles and is called classical thermodynamics.
To download this lecture notes kindly visit website or contact me
Topics include: visit my website (www.mech-4u.weebly.com)
1) introduction to thermodynamics
2) basics concepts of thermodynamics
3) types of system
4) properties of system
5) zeroth law of thermodynamics
6) concept of heat and work
7) properties of steam
8) properties of ideal gas
FellowBuddy.com is an innovative platform that brings students together to share notes, exam papers, study guides, project reports and presentation for upcoming exams.
We connect Students who have an understanding of course material with Students who need help.
Benefits:-
# Students can catch up on notes they missed because of an absence.
# Underachievers can find peer developed notes that break down lecture and study material in a way that they can understand
# Students can earn better grades, save time and study effectively
Our Vision & Mission – Simplifying Students Life
Our Belief – “The great breakthrough in your life comes when you realize it, that you can learn anything you need to learn; to accomplish any goal that you have set for yourself. This means there are no limits on what you can be, have or do.”
Like Us - https://www.facebook.com/FellowBuddycom
Thermodynamics: Thermodynamics system (open, close, and isolated), Thermodynamic Properties:
Definition and Units of -Temperature, Pressure (atmospheric, absolute and gauge). Volume. Internal
energy, Enthalpy, Concept of Mechanical work, Thermodynamics Laws with example- Zeroth Law, First
Law, Limitations of first law. Concept of heat Sink. Source, heat engine, heat pump,
refrigeration engine. 2nd Law of Thermodynamics statements (Kelvin Plank, Claussius), Numerical
on 2" law only.
Measurement: Measurement of Temperature (Thermocouple - Type according to temperature range
and application), Measurement of Pressure (Barometer, Bourdon pressure gauge, Simple U tube
Manometer with numerical).
Unit 1 thermodynamics by varun pratap singh (2020-21 Session)Varun Pratap Singh
Free Download Link (Copy URL):
https://sites.google.com/view/varunpratapsingh/teaching-engagements
Dear Students,
Please find the Basic Mechanical Engineering (TME-101, 2020-21 Session) Unit One notes in this section.
Topic cover in this section are:
UNIT-1: Fundamental Concepts and Definitions
Definition of thermodynamics, System, Surrounding and universe, Phase, Concept of continuum, Macroscopic & microscopic point of view. Density, Specific volume, Pressure, temperature. Thermodynamic equilibrium, Property, State, Path, Process, Cyclic and non-cyclic processes, Reversible and irreversible processes, Quasi-static process, Energy and its forms, Enthalpy.
Thermal testing, thermo mechanical and dynamic mechanical analysis & chem...Dr.S.Thirumalvalavan
Unit-V: THERMAL TESTING, THERMO-MECHANICAL AND DYNAMIC MECHANICAL ANALYSIS & CHEMICAL TESTING [OTHER TESTING].
Subject Name: OML751 Testing of Materials
Topics: Thermal Testing: Differential scanning calorimetry, Differential thermal analysis. Thermo-mechanical and Dynamic mechanical analysis: Principles, Advantages, Applications. Chemical Testing: X-Ray Fluorescence, Elemental Analysis by Inductively Coupled Plasma-Optical Emission Spectroscopy and Plasma-Mass Spectrometry.
B.E. Mechanical Engineering
Final Year, VII Semester, Open Elective Subject
[As per Anna University R-2017]
Material Characterization Testing, Unit IV; OML751 Testing of Materials Dr.S.Thirumalvalavan
Material Characterization Testing, Unit-IV
Subject Name: OML751 Testing of Materials
Topics: Material Characterization Testing [Optical microscopy, Electron microscopy-SEM, TEM. Diffraction techniques, Spectroscopy techniques. Electrical and Magnetic techniques.
B.E. Mechanical Engineering
Final Year, VII Semester, Open Elective Subject
[As per Anna University R-2017]
Unit-III Non Destructive Testing (NDT)
Subject Name: OML751 Testing of Materials
Topics: Various NDT tests [Visual inspection, Liquid penetrant test, Magnetic particle test, Thermography test, Radiographic test, Eddy current test, Ultrasonic test, Acoustic emission test]
B.E. Mechanical Engineering
Final Year, VII Semester, Open Elective Subject
[As per Anna University R-2017]
Unit-II Mechanical Testing
Subject Name: OML751 Testing of Materials
Topics: Various Mechanical Tests [Hardness, Tensile, Impact, Bend, Shear, Creep & Fatigue]
B.E. Mechanical Engineering
Final Year, VII Semester, Open Elective Subject
[As per Anna University R-2017]
Design procedure for Cast iron pulley, Flat belt drive, V belt drive, Chain d...Dr.S.Thirumalvalavan
Title: UNIT-I; Design Procedure of Cast iron pulley, Flat belt drive, V belt drive, Chain drive & Wire ropes.
Subject Name: ME8651 - Design of Transmission Systems (DTS) B.E. Mechanical Engineering
Third Year, VI Semester
[Anna University R-2017]
Subject Name: Testing of Materials (TOM)
Subject code: OML751
Unit I: Introduction to Materials Testing
B.E. Mechanical Engineering
Final year, VII Semester.
Open Elective Subject
[As per Anna university syllabus; R-2017]
HEAP SORT ILLUSTRATED WITH HEAPIFY, BUILD HEAP FOR DYNAMIC ARRAYS.
Heap sort is a comparison-based sorting technique based on Binary Heap data structure. It is similar to the selection sort where we first find the minimum element and place the minimum element at the beginning. Repeat the same process for the remaining elements.
NO1 Uk best vashikaran specialist in delhi vashikaran baba near me online vas...Amil Baba Dawood bangali
Contact with Dawood Bhai Just call on +92322-6382012 and we'll help you. We'll solve all your problems within 12 to 24 hours and with 101% guarantee and with astrology systematic. If you want to take any personal or professional advice then also you can call us on +92322-6382012 , ONLINE LOVE PROBLEM & Other all types of Daily Life Problem's.Then CALL or WHATSAPP us on +92322-6382012 and Get all these problems solutions here by Amil Baba DAWOOD BANGALI
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2. UNIT I BASIC CONCEPTS AND FIRST LAW 9+6
• Basic concepts - concept of continuum, comparison of microscopic and macroscopic
approach. Path and point functions. Intensive and extensive, total and specific
quantities. System and their types. Thermodynamic Equilibrium State, path and
process. Quasi-static, reversible and irreversible processes. Heat and work transfer,
definition and comparison, sign convention. Displacement work and other modes of
work .P-V diagram. Zeroth law of thermodynamics – concept of temperature and
thermal equilibrium– relationship between temperature scales –new temperature
scales. First law of thermodynamics –application to closed and open systems – steady
and unsteady flow processes.
@ S. Thirumalvalavan, AP/Mech, 5104 - AEC.
3. UNIT – 1 BASIC CONCEPTS AND FIRST LAW
• Thermodynamics is the science of energy transfer which deals with the
relations among heat, work and properties of systems.
• Thermodynamics = Thermo + dynamics
Heat + Motion
Heat Energy into POWER.
Thus, thermodynamics is basically the study of heat and power.
Today conservation of heat energy into power plays important role in power
generation, refrigeration etc.,
Ex: Burning of Coal (Water get heated to produce steam) – Turbine – Generator
– POWER output in the form of Electricity ;
Ex: Motorcycle = Fuel (Burned inside the Engine) – Heat – POWER output in the
form of Wheel rotation
@ S. Thirumalvalavan, AP/Mech, 5104 - AEC.
4. Application Area of Thermodynamics:
Energy transfer is present in almost all the engineering activities. Hence,
the principles of thermodynamics are playing vital role in designing all the
engineering equipments such as internal combustion engines, rockets, jet
engines, thermal and nuclear power plants, refrigerators etc.
Energy Capacity to do work
• Force = Mass x Acceleration (N)
F = m x a
• Weight = Mass x Acceleration due to gravity (g = 9.81 m/s2)
@ S. Thirumalvalavan, AP/Mech, 5104 - AEC.
5. Law of conservation of ENERGY Principle
Energy can be changed from one form to another from without losses
during energy interaction.
So, First law of thermodynamics is simply an expression of conservation
of energy. It considers only Quantity.
But, the Second law of thermodynamics considers both Quantity as well
as Quality.
@ S. Thirumalvalavan, AP/Mech, 5104 - AEC.
6. BASIC CONCEPTS
• Density (ρ) = mass / volume
m / v (kg / m3)
Wkt, Air density = 1 kg / m3 ; Water density = 1000 kg / m3
Mass – Scalar Quantity – Not depend on gravity
• Specific Weight (w) = weight / volume
W / V (N/m3 or kN/m3)
Weight – Vector quantity – Depend on gravity
• Specific volume (v) = volume / mass (m3/kg)
• Specific gravity (s) =
@ S. Thirumalvalavan, AP/Mech, 5104 - AEC.
7. BASIC CONCEPTS (Contd..)
• Pressure (p) = Force / Area
= F / A (N/m2)
It is defined as the force per unit area.
If we are dealing with, Liquid and gas – termed as Pressure ;
In solid – termed as Stress (Stress = Load/Area)
Various units of pressure,
1 pascal = 1 N/m2
1 Bar = 1x105 N/m2 = 100 kN/m2 = 100 000 N/m2
1 mm of Mercury (Hg) = 1 Torr = 133.3 N/m2
1 mm of water (H2O) = 9.80665 N/m2
Pressure, p --> 0.1 Mpa = 100 kpa = 105 pa = 105 N/m2 = 1 bar
1 Pa = 1 N/m2; 1 kpa = 1 kN/m2; 1 Mpa = 1000 kN/m2; 1 bar = 100 kN/m2 or kPa
@ S. Thirumalvalavan, AP/Mech, 5104 - AEC.
8. Figure 1. Pressure Relations
Temperature (T) : It is defined as the measure of velocity of fluid particles. It is a property which is used to
determine the degree of hotness or coldness or the level of heat intensity of a body.
T = t + 273 K
Where,
T – Temp. on Kelvin scale
t – Temp. on Celsius scale
Figure 2. Temperature Relationship
@ S. Thirumalvalavan, AP/Mech, 5104 - AEC.
9. HEAT (Q)
• Heat is defined as the energy crossing the boundary of a system due to the
temperature difference between system and surrounding. It is usually represented by
Q and expressed in Joule or kJ.
• Let, m be the mass of the substance heated from temperature T1 to T2, then the heat
transfer is given by
Q = m C (T2 – T1) = m C dT (Joule)
Where, C = specific heat of the substance
Note:
If Q is positive, heat is supplied to the system
If Q is negative, heat is rejected from the system
@ S. Thirumalvalavan, AP/Mech, 5104 - AEC.
10. • Specific heat capacity (C) : It is defined as “the Quantity of heat transfer required for
raising or lowering the temperature of unit mass of the substance through one degree”.
Denoted by C and is expressed in J/kg-K or kJ/kg-K
• Specific heat capacity at Constant volume (Cv) : It is defined as “the Quantity of heat
transfer required for raising or lowering the temperature of unit mass of the substance
through one degree when the volume remains constant”.
Heat transfer, Q = m Cv (T2 – T1) kJ
• Specific heat capacity at Constant Pressure (Cp) : It is defined as “the Quantity of heat
transfer required for raising or lowering the temperature of unit mass of the substance
through one degree when the pressure remains constant”.
Heat transfer, Q = m Cp (T2 – T1) kJ
• For any gas, Cp is always greater than Cv. (i.e., Cp > Cv)
• The ratio of two specific heats remains constant and is denoted by gamma (γ).
γ = Cp / Cv
For air, Cp = 1.005 kJ/kg K; Cv = 0.718 kJ/kg-K; γ = 1.4
@ S. Thirumalvalavan, AP/Mech, 5104 - AEC.
11. CHARACTERISTIC GAS EQUATION
General gas equation for ideal gas,
Where,
p – pressure in N/m2
V – volume in m3
T – temperature in oC
Taking R as constant,
PV = RT
If we consider mass ‘m’, then the Equ. becomes pV = mRT. This equation is known as
characteristic gas equation.
@ S. Thirumalvalavan, AP/Mech, 5104 - AEC.
12. TYPES OF THERMODYNAMICS
1. Statistical Thermodynamics is microscopic approach in which, the matter is
assumed to be made of numerous individual molecules. Hence, it can be regarded
as a branch of statistical mechanics dealing with the average behaviour of a large
number of molecules.
2. Classical thermodynamics is macroscopic approach. Here, the matter is considered
to be a continuum without any concern to its atomic structure.
@ S. Thirumalvalavan, AP/Mech, 5104 - AEC.
13. THERMODYNAMIC SYSTEM
1. System : A thermodynamic system is defined as a defined as a definite space or area
on which the study of energy transfer and energy conversions is made.
2. Boundary : The system and surroundings are separated by boundary. It may be fixed
or movable and real or imaginary.
3. Surroundings : Anything outside the system which affects the behavior of the system
is known as surroundings or the environment.
4. Control volume : A specified large number thermal device has mass flow in and out
of a system called as control volume.
5. Universe : A system and surroundings together comprise a universe.
Mass Mass
@ S. Thirumalvalavan, AP/Mech, 5104 - AEC.
14. CLASSIFICATION OF THERMODYNAMIC SYSTEMS
1. In Open System both the mass and energy transfer takes place. The open system is
often called as control volume.
2. A Closed System does not permit any mass transfer. But, only the energy transfer
takes place.
3. Isolated System : A system which is not affected by the surrounding, simply there is
no heat, work and mass transfer. It is an imaginary system. Ex: Entire universe.
@ S. Thirumalvalavan, AP/Mech, 5104 - AEC.
15. PROPERTIES
• It is defined as any measurable or observable characteristics of the substance when
the system remains in equilibrium state. Ex: Pressure, Temperature Volume, Entropy
etc.,
Properties are classified into two types,
i) Intensive or Intrinsic property : These properties are independent on the mass of
the system. If we consider a part of the system, these properties remain same.
Ex: Pr, Temp, Specific volume, density etc.,
ii) Extensive or Extrinsic property : These properties are dependent upon the mass of
the system. If we consider a part of the system, these properties have lesser value.
Ex: Mass, Volume, Total energy, weight etc.,
@ S. Thirumalvalavan, AP/Mech, 5104 - AEC.
16. STATE OF A SYSTEM
• STATE : It is the condition of the system at any particular moment. The state is
identified by the properties of the system such as pressure, volume, temperature etc.,
If the value of one property changes, the state will change to a different state
called a change of state. Ex: ICE Solid state WATER liquid state (Due to
temperature drop)
• PATH : The succession of state crossed through the control volume during change of
state in the thermodynamic system is called path.
THERMODYNAMIC PROCESS
1. Quasi-Static process
2. Reversible and Irreversible process
3. Flow and Non flow process
@ S. Thirumalvalavan, AP/Mech, 5104 - AEC.
17. CYCLE
• A series of state changes such that the final state is identical with the initial state is
known as cycle.
• If a thermodynamic system undergoes a series of processes and returns to its initial
position, then the process is called cyclic process.
• There are two types of cyclic processes,
(i) Closed cycle the working substance is recirculated again and again within the system
itself without taking any mass transfer.
(ii) Open cycle the working substance is exhausted to atmosphere after completing the
process. So, here both the mass and energy transfer take place.
@ S. Thirumalvalavan, AP/Mech, 5104 - AEC.
18. EQUILIBRIUM
• A system is said to be in equilibrium, if it does not tend to undergo any change of
state on its own accord.
• A system is said to be in thermodynamic equilibrium, then it should satisfy the
following three conditions of equilibrium.
(i) Mechanical Equilibrium A system is said to be in mechanical equilibrium, when
there is no unbalanced forces acting on it.
(ii) Thermal equilibrium A system is said to be in thermal equilibrium, when there is no
temperature difference throughout the system.
(iii) Chemical Equilibrium A system is said to be in chemical equilibrium, when there is
no chemical reaction throughout the system.
@ S. Thirumalvalavan, AP/Mech, 5104 - AEC.
19. WORK TRANSFER (W)
• Work is an energy interaction between system and surroundings.
• Work can be defined as the energy interaction which is not caused by the
temperature difference between system and surroundings.
Specifically, it is the energy transfer associated with force acting through a distance.
Work = force x distance moved
W = F x x N-m or kJ/kg
POWER : The Work done per unit time is called power unit is kJ/sec or kW.
• Work done BY the system is denoted as Positive work
• Work done ON the system is denoted as Negative work
Modes of Work transfer : (i) Mechanical work (ii) Non-mechanical work
@ S. Thirumalvalavan, AP/Mech, 5104 - AEC.
20. POINT AND PATH FUNCTIONS
From above figure, the properties like pressure and volume do not depend upon the
path [ 1 – C – 2 or 1 – B – 2 ] followed by the gas. It requires end points only. Therefore,
these properties are called as point function.
Some properties like work transfer, heat transfer etc., are dependent upon the path
followed by a gas. These properties are called as path function.
@ S. Thirumalvalavan, AP/Mech, 5104 - AEC.
21. ZEROTH LAW OF THERMODYNAMICS
• It states that “When two systems are in thermal equilibrium with the third system
separately, then they themselves are in thermal equilibrium with each other”.
• A system A in thermal equilibrium with another system B. Also let another system C is
thermal equilibrium with the system B. Then from Zeroth law of thermodynamics, the
system A is in thermal equilibrium with the system C. Hence, A and C are at same
temperature.
@ S. Thirumalvalavan, AP/Mech, 5104 - AEC.
22. FIRST LAW OF THERMODYNAMICS
• It states that “When a system undergoes a cyclic process, then the net heat transfer is
equal to the net work transfer”.
• Mathematically,
• It may be stated, the heat and work are mutually convertible.
• In general, for any thermodynamic systems, the first law of thermodynamics can be
written in the form of following equation.
Heat transfer = Work done + Change in internal energy
Q = W + ∆U
@ S. Thirumalvalavan, AP/Mech, 5104 - AEC.
23. LIMITATIONS OF FIRST LAW OF THERMODYNAMICS
1. First law of thermodynamics does not specify the direction of flow of heat and
work. i.e., whether the heat flows from hot body to cold body or cold body to hot
body.
2. The heat and work are mutually convertible. The work can be converted fully into
heat energy. But heat cannot be converted fully into mechanical work.
This violates the foresaid statements. A machine which violates the First law of
thermodynamics is known as Perpetual Motion Machine (PMM-1) of the first kind
which is impossible.
PMM-1 is a machine which delivers work continuously without any input.
Thus, the machine violates first law of thermodynamics.
@ S. Thirumalvalavan, AP/Mech, 5104 - AEC.
24. Unit Conversion (To Remember)
We know that,
• Kilo – 103 ; Mega – 106 ; Giga – 109 ; Terra – 1012 ;
• 1 watt = 1 J/sec
• 1 kW = 1 kJ/sec
• 1 J/s = 1 W
• 1 tonne = 3.5 kW
• 1 Hr = 3600 sec
• m x103 mm; mm ÷103 m
• km x103 m; m ÷103 km
• km/s x103 m/s; m/s ÷103 km/s
• min x60 sec; sec ÷60 min
• kJ x103 J; J ÷103 kJ
@ S. Thirumalvalavan, AP/Mech, 5104 - AEC.
25. Problems on Basics
1. During a flow process 5kW paddle wheel work in supplied while the internal energy of the
system increases in one minute in 200kJ. Find the heat transfer when there is no other form
of energy transfer.
Given Date:
Work done, W = -5 kW (-ve sign; Work is supplied)
Internal energy, ∆U = 200 kJ/m = 3.33 kJ/s
To find:
Heat transfer, Q = ?
Solution: By first law of thermodynamics,
Q = W + ∆U
= -5 + 3.33
Q = -1.67 kW
Result: Heat transfer, Q = -1.67 kW [ -ve sign indicates that the heat is transferred from the
system] @ S. Thirumalvalavan, AP/Mech, 5104 - AEC.
Unit conversion:
(min Sec ; ÷ by 60)
1 kW = 1 kJ/sec
26. Problems on Basics
2. A liquid of mass 18kg is heated from 25oC to 85oC. how much heat transfer is required?
Assume Cp for water is 4.2 kJ/kg-K.
Given Date:
Mass, m = 18 kg
Initial temp, T1 = 25 oC = 25 + 273 = 298 K (oC K ; +273)
Final temp, T2 = 85 oC = 85 + 273 = 358 K (oC K ; +273)
Cp for water = 4.2 kJ/kg-K (Cp = Specific heat capacity at Const. Pressure)
To find: Heat transfer, Q = ?
Solution: From Specific heat capacity at Constant Pressure (Cp) definition wkt,
Q = m Cp ( T2 – T1)
= 18 x 4.2 x (358 - 298)
Q = 4536 kJ
Result: Heat transferred, Q = 4536 kJ
@ S. Thirumalvalavan, AP/Mech, 5104 - AEC.
Unit conversion:
So, Balance : kJ
27. Problems on Basics
3. A closed system receives an input heat of 450 kJ and increases the internal energy of the
system for 325 kJ. Determine the work done by the system.
Given Date:
Heat received, Q = 450 kJ
Change in Internal energy, ∆U = 325 kJ
To find: Work done, W = ?
Solution: By first law of thermodynamics,
Q = W + ∆U
W = Q - ∆U
= 450 – 325
Q = 125 kJ
Result: Work done, W = 125 kJ
@ S. Thirumalvalavan, AP/Mech, 5104 - AEC.