Design method capable of expanding air resonance security boundary of helicopter

A technology of safety boundary and design method, applied in the direction of rotorcraft, motor vehicles, aircraft parts, etc., can solve problems such as limiting helicopters, and achieve the effect of improving flight safety and rigidity
CN104890867AInactive Publication Date: 2015-09-09CHINA HELICOPTER RES & DEV INST
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Patent Information

Authority / Receiving Office
CN · China
Patent Type
Applications(China)
Current Assignee / Owner
CHINA HELICOPTER RES & DEV INST
Publication Date
2015-09-09
Estimated Expiration
Not applicable · inactive patent

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Abstract

The invention discloses a design method capable of expanding an air resonance security boundary of a helicopter, relates to a design method capable of expanding the security boundary of air resonance appearing in the helicopter in the flying speed and force lifting overloading state, and belongs to the technical field of dynamic design of the helicopter. According to the rotor blade operation pneumatic environment of the flying state stipulated by a flight envelope which needs to consider a cover and properly exceeds the performance requirement of the helicopter, unstability of the air resonance is analyzed, and the pitch control stiffness is improved to the air resonance insensitive range; the width of paddle rear edge adjusting sheets and distribution of the paddle rear edge adjusting sheets in the expanding direction are increased, so that an equivalent aerodynamic center moves backwards; and the paddle aeroelasticity coupling characteristics are improved so as to expand the air resonance security boundary.
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Description

technical field

[0001] The invention belongs to the technical field of helicopter dynamics design, and in particular relates to a safety boundary design method for expanding helicopter flight speed and lift overload state to generate aerial resonance. Background technique

[0002] With the continuous development of helicopter rotor design technology, the phenomenon of coupling shimmy instability between the rotor and the body not only exists on the ground, but also in the air. The classic ground resonance design technology that only considers the multi-blade shimmy motion of the rotor cannot meet the needs of new rotor technologies, The need for new configuration development. Composite rotor blades, spherical flexible hubs, bearingless and hingeless rotors all make the instability caused by the coupling between the rotor and the body very different from the original ground resonance phenomenon, while the spherical flexible hub, bearingless and The hingeless rotor helicopter...

Claims

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