Otto cycle

American  

noun

Thermodynamics.

1. an idealization of the thermodynamic cycle of the internal combustion engine with air as the working substance: intake of air at atmospheric pressure, then adiabatic compression, then ignition with an increase of pressure and temperature at constant volume, then adiabatic expansion and performance of work, then a drop to atmospheric pressure at constant volume and a rejection of heat to the environment, then the exhaust of air at constant pressure.

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Otto cycle British  

noun

1. an engine cycle used on four-stroke petrol engines ( Otto engines ) in which, ideally, combustion and rejection of heat both take place at constant volume Compare diesel cycle

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Etymology

Origin of Otto cycle

1885–90; named after Nikolaus August Otto, 1832–91, German engineer and inventor

Example Sentences

See Examples For:

Otto cycle

To make the engine operate, the researchers reproduced an Otto cycle inside a superconducting circuit.

From Science Daily ● Aug. 14, 2026

The Otto cycle is a thermodynamic process also used in car engines and other conventional machines.

From Science Daily ● Aug. 14, 2026

In the Otto cycle, heat transfer occurs along path DA.

From Textbooks ● Aug. 12, 2015

Just as discussed for the Otto cycle in the previous section, this means that efficiency is greatest for the highest possible temperature of the hot reservoir and lowest possible temperature of the cold reservoir.

From Textbooks ● Aug. 12, 2015

Assuming that we are still dealing with the Otto cycle engine, the cam or side shaft will revolve at precisely half the speed of the crank shaft.

From Gas and Oil Engines, Simply Explained An Elementary Instruction Book for Amateurs and Engine Attendants by Walter C. Runciman