Otto cycle

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.

Otto cycle

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

Word History and Origins

Origin of Otto cycle¹

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

Word History and Origins

Origin of Otto cycle¹

C19: named after Nikolaus August Otto (1832–91), German engineer

Example Sentences

The Otto Cycle.—The term "four-cycle" motor, or Otto engine, has its origin in the manner in which the engine operates.

From Project Gutenberg

The greater number of engines used in automobiles to-day are of the kind known as the Otto cycle, or four-cycle, engine.

From Project Gutenberg

About 1900 the Gasmotoren Fabrik Deutz built an Otto cycle engine of 1000 b.h.p. having four cylinders each 33 in. diameter and 39.3 in. stroke, speed 135 revolutions per minute.

From Project Gutenberg

Gas engines operating on the Otto cycle are usually of the single acting open cylinder type up to about 200 b.h.p., but for the larger engines closed cylinders of the double acting type are used.

From Project Gutenberg

The “Rattler” was fitted with five-cylinder Otto cycle engines and suction gas-producers giving 500 i.h.p.; and has sailed some 1500 m. under gas power only.

From Project Gutenberg