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

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

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

Figure 15.20 PV diagram for a simplified Otto cycle, analogous to that employed in an internal combustion engine.

From Textbooks ● Aug. 12, 2015

Also the difference between Otto cycle and Diesel becomes slight as the compression ratios come closer together.

From The First Airplane Diesel Engine: Packard Model DR-980 of 1928 by Meyer, Robert B.