Carnot cycle

American  

noun

Thermodynamics.

1. an ideal cycle of reversible engine operations in which a substance at one temperature is compressed adiabatically to a second temperature, expanded isothermally at the second temperature, expanded adiabatically from the second temperature to the first temperature, and compressed isothermally at the first temperature.

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Carnot cycle British  

noun

1. an idealized reversible heat-engine cycle giving maximum efficiency and consisting of an isothermal expansion, an adiabatic expansion, an isothermal compression, and an adiabatic compression back to the initial state

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Etymology

Origin of Carnot cycle

After N. L. S. Carnot

Example Sentences

See Examples For:

Carnot cycle

The concept is illustrated by the Carnot cycle, an idealized model that defines the maximum theoretical efficiency of a heat engine by carefully regulating the movement of heat between hot and cold regions.

From Science Daily ● Jul. 11, 2026

Any engine that uses the Carnot cycle enjoys the maximum theoretical efficiency.

From Textbooks ● Aug. 12, 2015

The second law of thermodynamics can be restated in terms of the Carnot cycle, and so what Carnot actually discovered was this fundamental law.

From Textbooks ● Aug. 12, 2015

We noted that for a Carnot cycle, and hence for any reversible processes, Qc / Qh = Tc / Th .

From Textbooks ● Aug. 12, 2015

The formula is the same as that for the Carnot cycle with the same range of temperature in expansion.

From Encyclopaedia Britannica, 11th Edition, Volume 13, Slice 2 "Hearing" to "Helmond" by Various