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Defnition Thermodynamics is derived rom two words:

‘Thermo’ which means ‘Heat energy’ and‘Dynamics’ which means ‘conversion’ or

‘transormation’

Concisely, thermodynamics is a division o sciencethat deals with conversion o energy rom one orm

to another

 The main orms o energy o interest inengineering thermodynamics are heat and wor

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Defnition contd!"or is the orm o energy useul in

dis#lacement o a $ody

Heat is the orm o energy transerred due totem#erature gradient $etween two $odies

(Joules)DistanceForceWork    ×=

(Joules) differenceeTemperatur SpecificMassHeat ××=

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Applications of Engineering

Thermodynamics%ngineering a##lication o thermodynamic

#rinci#les is the design o various systemsusing &uid #ro#erties to cause energytransormation

'##lications in design o heat engines,

rerigeration machines, air conditioningsystems

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Scope of Thermodynamics

(t is limited to macrosco#ic #ro#erties omatter i!e! #ro#erties o large num$er o#articles o systems

(t considers the initial and fnal states o asystem and not the mechanism o the #rocess

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Important uid properties inthermodynamics

Density

)#ecifc heat ca#acity

 Tem#erature

(nternal energy

%ntro#y

%nthal#y

*ressure)#ecifc volume

+ass

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Heat Engines

Heat engines are devices designed or the

#ur#ose o converting other orms o energy0usually in the orm o heat1 to wor! Heat

engines di3er considera$ly rom one another, $ut

all can $e characteri4ed $y the ollowing:

5! They receive heat rom a high6tem#eraturesource 0solar energy, oil urnace, nuclear reactor,

etc!1!

7! They convert #art o this heat to wor 0usually

in the orm o a rotating shat1!

8! They re9ect the remaining waste heat to a low6

tem#erature sin 0the atmos#here, rivers, etc!1!

! They o#erate on a cycle!