Otto cycle


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Otto cycle

n
(General Engineering) 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
[C19: named after Nikolaus August Otto (1832–91), German engineer]
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In connection with the replacement of lto cogeneration units with gasoline engines with otto cycle, The heat distribution in the cogeneration unit engine room will also be reconstructed.
A 2.4 Atkinson cycle petrol engine replaces the previous regular Otto cycle 2.0 litre.
In the automotive industry, ethanol has been used in Otto cycle engines; the use of ethanol has led to the development of the so called "flex" technology that allowed operation with 100% gasoline or ethanol as fuel.
A larger proportion of constant volume combustion by an increased fuel injection rate, advanced injection timing, HCCI (homogeneous charge compression ignition) combustion [1], PCI (premixed compression ignition) combustion [2] etc., have been investigated, since the thermal efficiency of the Otto cycle is ideally higher than other reciprocating engine cycles [3].
The isothermal compressor could be used as the compression stage in an Otto cycle engine, enabling the use of a higher compression ratio and improving efficiency.
The clever bit is that by using variable valve timing the engine can swap from the conventional Otto cycle to the Atkinson cycle (in which the inlet valves are held open longer and allow air to reverse flow through the inlet manifold) to save fuel at cruising speeds.
For decades, efforts to meet ever-increasing standards like this have depended on a thorough understanding of Otto cycle dynamics in internal combustion engines and development of ways to change emissions through exhaust gas recirculation (EGR).
The Dual Variable Valve Timing with intelligence (VVT-iW) system allows the engine to start in the Otto cycle and then run in the more fuel efficient Atkinson cycle (there is late intake valve closing during the Atkinson cycle which reduces pumping losses and boosts fuel economy; the "W" in the engine descriptor nomenclature stands for "wide," as in a wider intake cam timing control).
[8] applied the Miller cycle into an Otto cycle natural gas engine and the SFC and power output of the engine decreased.
When fully developed with its turbocharged and Air-Hybrid components, the engine is expected to achieve significant gains in fuel efficiency--the most since the inception of the Otto cycle over 130 years ago, according to the company.