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US 4,012,165 AGranted
Fan structure
AssigneeUnited Technologies Corporation
InventorAlfred Henry Kraig
Life of this patent
Estimating the term…
Abstract
A fan structure which is particularly well suited for use in a high tip speed turbofan, gas turbine engine is disclosed. Various construction details accommodate both subsonic and supersonic flow across the fan blades. The system is built around compression shock wave phenomenon which are utilized to stably convert a portion of the dynamic energy of a supersonic stream to pressure energy within a subsonic stream.
Claims3
In a turbofan engine having a rotor which is mounted for rotation with respect to a stationary fan case, the improvement which comprises:
- a plurality of circumferentially spaced fan blades extending radially from the rotor toward the fan case wherein each fan blade has
- an inward region which is contoured for the conversion of dynamic energy within subsonic and low supersonic streams to pressure energy and
- an outward region which is contoured for the conversion of dynamic energy within a high supersonic stream to pressure energy within a subsonic stream and wherein said contour of the outward region is adapted to form between each pair of adjacent blades
- a convergent passage for the gradual deceleration of the supersonic stream and
- a throat downstream of the convergent passage for containment of a normal shock wave between adjacent blades;
- a mid-span shroud positioned on each blade to separate said inward subsonic and low supersonic region from said outward high supersonic region;
- and
- at least one starting and stabilizing door in said stationary case which is radially opposes the fan blade tips and which is moveable with respect thereto to vary the area of the convergent passage and of the throat for positioning the shock wave at the throat.
5 more elements
Dependencies are inferred from the claim text.