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Clearance Volume: The minimum

volume formed in cylinder when piston isat TDC

Swept Volume: Volume displaced by the

piston from TDC to BDC

Compression Ratio: The ratio of themax. vol. formed in the cylinder to the

minimum (clearance) volume

Compression Ratio r of the Engine

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Complexities in studying IC Engines:

Study of performance of IC Engines would take into account

Combustion processes occuring

The composition of working fluid changes from air and fuel to

combustion products

Effects of irreversibilities i.e. Friction, Temp and Press gradients

Heat transfer between the gases in the cylinder and cylinder walls

Intake the charge and exhaust the combusted products

To reduce the analysis to manageable level, following assumptions are

utilized commonly known as air-standard assumptions

Air-Standard Analysis

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