2. CONTENTS
• INTRODUCTION OF HEAT ENGINE
• EXPLANATION OF HEAT ENGINE
• EFFICIENCY OF HEAT ENGINE
• CLASSIFICATION OF ENGINE
• 3D MODEL OF STEAM ENGINE
• CARNOT ENGINE
• CARNOT CYCLE
• CARNOT EFFICIENCY
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3. EXPLANATION OF HEAT ENGINE:
Let,
Q1= Heat transferred to the system
Q2= Heat rejected from the system
W1= Work done upon the system
W2= Work done by the system
The net heat transfer in a cycle to the Heat engine
Qnet = Q1-Q2
And net work transfer
Wnet = W2-W1
By the first law of thermodynamics
∑Q=∑W ……. For a closed cycle
Qnet = Wnet
or
Q1-Q2 = W2-W1
INTRODUCTION: HEAT ENGINE
• A heat engine cycle is a thermodynamic cycle in which there is a net heat
transfer to the system and a net work transfer from the system. The
system which executes a heat engine cycle is called a heat engine.
• It takes heat from a reservoir then does some work like moving a piston,
lifting weight, etc and finally discharges some heat energy into the sink.
A
GINE
k done by the
must be supplied to
le/total heat input
A
A
A
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5. CARNOT ENGINE
• The efficiency of a typical automobile engine is
less than 30%.
• This seems to be wasting a lot of energy.
• What is the best efficiency we could achieve?
• What factors determine efficiency?
• The cycle devised by Carnot that an ideal engine
would have to follow is called a Carnot cycle.
• An (ideal, not real) engine following this cycle is
called a Carnot engine.
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6. • Carnot engine is a theoretical thermodynamic
cycle proposed by Leonard Carnot.
• It gives the estimate of the maximum possible
efficiency that a heat engine during the
conversion process of heat into work and
conversely, working between two reservoirs, can
possess.
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