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Brayton cycle

The Brayton cycle is a power cycle generally associated with the gas turbine. It is unique among power cycles in being an open system.


A Brayton engine consists of three components:

Ambient air is drawn into the compressor, where it is pressurized -- a theoretically isentropic process. The compressed air then runs through a combustion chamber, where fuel is burned, heating that air -- a constant-pressure process, since the chamber is open to flow in and out. The heated, pressurized air then gives up its energy, expanding through a turbine (or series of turbines) -- another theoretically isentropic process. Some of the work extracted by the turbine is used to drive the compressor.

Since neither the compression nor the expansion can be truly isentropic, losses through the compressor and the turbine represent sources of inescapable working inefficiencies.

In general, increasing the compression ratio is the most direct way to increase the overall power output of a Brayton system


The efficiency of a Brayton engine can be improved in the following manners:

See also: