High bypass-ratio turbofan jet engine
AssigneeJapan Aerospace Exploration Agency
InventorsRyoji Yanagi, Hitoshi Fujiwara
Life of this patent
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Abstract
To provide a turbofan jet engine which is capable of increasing the bypass ratio without increasing the fan diameter, and of reducing air resistance acting on the engine, a front fan duct that discharges air compressed by a front fan to the atmosphere and an aft fan duct that introduces air into an aft fan are disposed such as to change cross-sectional shapes thereof by rotating around a core engine in a counterclockwise direction, so that the cross-sectional geometric relationship between the front fan duct and the aft fan duct at a position immediately posterior to the front fan and a cross-sectional geometric relationship between the front fan duct and the aft fan duct at a position immediately anterior to the aft fan are inverted.
Claims5
A high bypass-ratio turbofan jet engine, comprising:
- a core engine that generates a propulsive force by ejecting combustion gas rearward;
- and
- a fan that generates a propulsive force by ejecting an airflow rearward while compressing the airflow, and suppresses a noise of an exhaust stream of the core engine,
- wherein the fan includes a front fan disposed in the vicinity or upstream of a compressor of the core engine, and an aft fan disposed in the vicinity or downstream of a turbine, and
- wherein a front fan duct that discharges air compressed by the front fan to the outside and an aft fan duct that introduces air into the aft fan are disposed along a longitudinal direction of the core engine in such a manner to spirally twist relative to each other such that cross-sectional shapes of the front fan duct and the aft fan duct change relative to each other by rotating around the core engine in one direction.
Dependencies are inferred from the claim text.