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Introduction:

Thermodynamics is an exciting and fascinating subject that deals with

energy,which is essential for sustenance of life, and thermodynamics has long been an

essential part of engineering curricula all over the world .It has a broad application area

ranging from microscopic organism to common household appliance ,transportation

vehicle ,power generation systems ,and even philosophy .This Course material contains

sufficient materials for two sequential courses in thermodynamics .

Objectives

This course material is intended for use as a test book by undergraduate engineering

students in their sophomore, and as a reference book for practicing engineers. The

objective of this text are

. To cover the basic principles of thermodynamics.

!. To present a wealth of real world engineering examples to give students a

feel for how thermodynamics is applied in engineering practice .

". To develop an intuitive understanding of thermodynamics by emphasi#ing the

physics and physical arguments.

It is our hope that this book, through its careful explanations of concepts and its use of

numerous practical examples and figures, helps students develop the necessary skills tobridge the gap between knowledge and the confidence to properly apply knowledge.

Unit I

Overview of Unit -01

This unit consists of seven lesson of teaching, in the first lesson we will study

$asic of Thermodynamics, %acroscopic and microscopic approach .and its definitions,

.In the second lesson we will study system types with pictorial representation,

introduction to properties. In third lesson we will study &roperties i.e intensive and

extensive properties with examples in addition to that we study the definition of state,

path and process. In fourth lesson we study thermodynamic equilibrium, types of

equilibrium with examples .In fifth lesson we study about 'iathermia wall, (uasi)static

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process and some basic definition to solve the numerical problems like specific volume,

pressure, temperature* +eroth law of thermodynamics etc. In sixth lesson we study

Temperature scale factor conversion like ahrenheit to Celsius and Celsius to ahrenheit

and few -umerical problems were solved .In seventh lesson we study about

%easurements and internal fixed points.

Objective of Unit -01

t the end of this unit we shall understand that/

$asic concepts about the Thermodynamics

pplication of Thermodynamics with examples

Cycles, 0quilibrium and their types with examples and sketches

Temperature scale factor conversion and its utility in engineering science

ew numerical problems in 1niversity aspects.

Lesson -01

1.1 BASIC CONC!"S AN# #$INI"IONS

Objective:

t the end of lesson you shall understand that

The 2tatistical thermodynamics and classical thermodynamics are different based on the

requirements the type can be chosen. The temperature and its fixing with numerical

problems. nd how the classification and definitions are varying in equilibrium, cycle

with examples. In overall you will be able to through about what is thermodynamics how

it plays its vital role .

Introduction:

In this lesson you will be able to solve the numerical problems in energy

conversion and, in internal fix points. %ore over you will get thorough knowledge in

$asic thermodynamics.

1.1 "%er&od'n(&ics:-

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It can be defined as the science which deals with the relation between heat, work

and properties of the system.

A))*ic(tions:

'esigning work producing machine 3 4eat engine, 2team engine, 5as

Turbine

'esigning work bsorbing machine 3 6efrigerator, ir compressor

-o work transfer systems ) boiler, condenser, and furnace.

7here no work is transferred, the Thermodynamic problem involve the use of

heat to produce the change in state or the transfer of mass with a chemical reaction, as in

the combustion of a fuel.

It is the science dealing with energy and its transformation.

0nergy can be viewed as ability to cause the change the name thermodynamics is

derived from greek word 8Therm9 means heat and 8dynamics9 means power, which is the

most descriptive of the earlier efforts to convert heat into power.

1.+ ,(crosco)ic (nd &icrosco)ic ())ro(c%:

,(crosco)ic ())ro(c%: In the study of the thermodynamics one can adopt two

different approaches namely macroscopic and microscopic. In macroscopic approach

W QP, V, T,

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suppose a certain amount of gas is trapped in a container, one can measure the volume

occupied by the gas by measuring the diameter and height of the cylinder. The pressure

exerted by the gas by measuring the diameter and height of the cylinder. The pressure

exerted by the gas can be measured with the help of pressure gauge and its temperature

can be measured with the help of thermometer. Then the state of the gas can be described

by specifying the pressure, volume and temperature. The values of these variables which

can be measured very easily. Thus in macroscopic approach.

. The structure of the matter is not considered.

!. :nly a few variables are used to describe the state of the matter under consideration

". The values of the variables used to describe the state of the matter are easily

measurable.

In classical thermodynamics, we adopt macroscopic approach.

,icrosco)ic ())ro(c%: In microscopic approach a same gas can be considered as

consisting of a large number of small particles each of which moves at random with

independent velocity. The state of each particle can be specified in terms of position co)

ordinates ;xi, yi, #i< and the momentum component ;&xi, &yi, i

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!. The variables choose to describe the state of the matter cannot be measured easily and

preciously.

". knowledge of structure of matter under consideration is essential.

In statistical thermodynamics, we adopt microscopic approach.

S'ste&:

2ystem or thermodynamic system is defined as a quality of matter or a region in

space upon which attention is concentrated in the analysis of a problem.

Surroundin:

The mass ;matter< or a region outside the system is called surrounding or

everything external to the system is called surrounding.

Bound(r':

The real or imaginary surface that separates the system from its surrounding is

called the boundary. The boundary of a system can be fixed or movable.

Note: The boundary is a contact surface sheared by both system and surrounding. The

boundary has #ero thickness and thus it can neither contain any mass nor occupy any

volume in space.

2ystem and its surrounding forms universe

2ystem

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1niverse $oundary

2urrounding

2ystem and surroundings from &iston cylinder arrangement

2urrounding

Su&&er':

4ere we learnt the Classical and statistical thermodynamics and their explanation.

7e studied how the system is classified and what are surroundings and boundaries.

Lesson-0+

Objective:

t the end of the lesson you shall understand that

2ystems are being considered to study about the energy transformation

Isolated system has fixed mass and energy

systemBoundary

Surrounding

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&roperties are required to mention about the characteristics of the

2ystem

Introduction:

In this lesson you will study about system, and its types with examples.

>ou will get introduction about properties and its lists with units.

1. "%ree c*(ssific(tions of s'ste&:

;a< Closed 2ystem

;b< :pen 2ystem

;c< Isolated 2ystem.

/( C*osed s'ste& /Contro* &(ss: Closed system is a identifiable collection of matter

on which attaintion is focused during thermodynamic analysis of problem. closed

system consists of fixed amount of mass and no mass can cross its boundary i.e., no mass

can enter or leave a closed system.

C%(r(cteristics of ( c*osed s'ste& bound(r':

. The si#e, shape and orientation of a system, boundary with respect to a stationary

observer can change.

!. %aterial ;mass< cannot cross the system boundary either or both direction.

". There can be heat and ? or work interaction across the system boundary.

&iston

%ass ;-oes