a jet engine having a large impeller that takes in air, part of which is used in combustion of fuel, the remainder being mixed with the products of combustion to form a low-velocity exhaust jet.
Also called: high bypass ratio enginea type of by-pass engine in which a large fan driven by a turbine and housed in a short duct forces air rearwards around the exhaust gases in order to increase the propulsive thrust
A type of gas turbine in which the fan driving air into a turbojet also forces additional air around the outside of the turbine, combining it with the exhaust of the turbojet to provide thrust. Turbofans are quieter than simple turbojets and somewhat more fuel efficient, and are widely used in commercial aircraft.
