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

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

From Textbooks • Aug. 12, 2015

Figure 15.21 This Otto cycle produces a greater work output than the one in Figure 15.20, because the starting temperature of path CD is higher and the starting temperature of path AB is lower.

From Textbooks • Aug. 12, 2015

Along path BC of the Otto cycle, heat transfer Qh into the gas occurs at constant volume, causing a further increase in pressure and temperature.

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

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

From The Story of Great Inventions by Burns, Elmer Ellsworth