Turbofan engine

Animation of a 2-spool, high-bypass turbofan

1. Low-pressure spool
2. High-pressure spool
3. Stationary components

1. Nacelle
2. Fan
3. Low-pressure compressor
4. High-pressure compressor
5. Combustion chamber
6. High-pressure turbine
7. Low-pressure turbine
8. Core nozzle
9. Fan nozzle

The turbofan or fanjet is a type of airbreathing jet engine that is widely used in aircraft propulsion. The resulting turbofan, with reasonable efficiencies and duct loss for the added components, would probably operate at a higher nozzle pressure ratio than the turbojet, but with a lower exhaust temperature to retain net thrust. Examples of this configuration are the long-established Garrett TFE731, the Honeywell ALF 502/507, and the recent Pratt & Whitney PW1000G. Most of the configurations discussed above are used in civilian turbofans, while modern military turbofans (e.g., Snecma M88) are usually basic two-spool. This can be achieved by raising the overall pressure ratio (combustor inlet pressure/intake delivery pressure) to induce more airflow into the core and by increasing turbine inlet temperature. Because modern civil turbofans operate at low specific thrust, they require only a single fan stage to develop the required fan pressure ratio. ^ Ferrante, P. G.; Copiello, D.; Beutke, M., "Design and experimental verification of 'true zero-splice' acoustic liners in the universal fan facility adaptation (UFFA) modular rig", 17h AIAA/CEAS Aeroacoustics Conference, Portland, OR, AIAA-2011-2728.