Otto cycle
Proper noun
Meaning
Otto cycle
The basic thermodynamic cycle of the normal four-stroke internal combustion engine: isentropic compression, constant-volume heat addition, isentropic expansion, and constant-volume heat rejection.
Examples
Comparing the two formulae it can be seen that for a given compression ratio ( r ), the ideal Otto cycle will be more efficient.
In contrast, the idealized Otto cycle of a gasoline engine approximates a constant volume process during that phase.
Other cycles, such as the Otto cycle, Diesel cycle and Brayton cycle, can be analyzed from the standpoint of the Carnot cycle.
However ammonia cannot be easily used in existing Otto cycle engines because of its very narrow flammability range and there are also other barriers to widespread automobile usage.
Furthermore, the ideal Otto cycle formula stated above does not include throttling losses, which do not apply to diesel engines.
The Otto cycle by comparison has both the heat addition and rejection at constant volume.