Otto Cycle Efficiency Calculator

Efficiency (η):

Compression Ratio (r):

Heat Capacity Ratio (γ):

How This Is Calculated

$$ \eta = 1- \frac{1}{r^{\gamma - 1}} $$ where:

η = Efficiency (Dimensionless)

r = Compression Ratio (Dimensionless)

γ = Heat Capacity Ratio (Dimensionless)

Assumptions

The working fluid behaves as an ideal gas.
Specific heats remain constant.
Compression and expansion processes are adiabatic.
There is perfect mixing of the air and fuel.

Related Calculators

Otto Cycle Compression Ratio

Otto Cycle Heat Added (Combustion Process)

Otto Cycle Heat Rejected (Exhaust Process)

Otto Cycle Pressure

Otto Cycle Temperature