Aerofoil arrangement
OwnerGraham Bond Groveinventor
Life of this patent
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Abstract
Upper surface (13) of an aerofoil (or rotor blade) is provided with nozzles or slots (14, 16) at leading portion (15) and trailing portion (17) to assist attachment of airflow by discharging gas towards trailing edge (11). Gas discharged may be heated, eg coming from rocket-type combustion chambers within the aerofoil. The aerofoil may be adjustable between high profile (as shown) and low profile (for supersonic flight) using jacks that pivot sections of upper surface (13) at leading and trailing edges (10-11).
Claims42
An aerofoil having a chord length and a depth and which is adjustable between a high profile configuration for subsonic flow and a low profile configuration for supersonic flow, the aerofoil having an initial angle of attack to oncoming airflow of at least about 22 degrees, the aerofoil including a leading edge which generates a subsonic leading edge breakaway flow in the high profile configuration that comes from beneath the leading edge, an upper surface having a leading portion inclined away from the leading edge and a trailing portion rearward of the leading portion, a lower surface, and a trailing edge, wherein in the high profile configuration the depth of the aerofoil is at least about 30% of the chord length of the aerofoil so that the aerofoil is effective to reattach the leading edge breakaway flow and enables the aerofoil to operate with the initial angle of attack of at least about 22 degrees, and at least one opening provided along the leading portion of the upper surface and arranged to discharge a sufficient volume of gas away from the leading edge to reattach the leading edge breakaway flow to the upper surface.
An aerofoil having an initial angle of attack to oncoming airflow of at least about 22 degrees;
- a profile including a chord length and a depth, wherein the depth of the aerofoil is at least about 30% of the chord length of the aerofoil, the profile being such that a leading edge of the aerofoil generates a subsonic leading edge breakaway flow that comes from beneath the leading edge;
- a substantially continuous upper surface having a leading portion inclined away from the leading edge, and a trailing portion angled toward a trailing edge;
- a lower surface;
- and at least one opening provided in the leading portion of the upper surface and arranged to discharge gas away from the leading edge with the profile of the aerofoil being effective and the discharged gas being of sufficient volume to reattach the leading edge, breakaway flow to the upper surface, the profile further being such that the aerofoil is able to operate with the initial angle of attack of at least about 22 degrees.
Dependencies are inferred from the claim text.