초록 ▼

An active control device for reducing high-speed impulsive ("HSI") and blade vortex interaction ("BVI") noise in a rotor aircraft, such as a helicopter, is disclosed. The system comprises a plurality of rotor blades extending radially in spaced relationship from a central hub, each of the blades hav

An active control device for reducing high-speed impulsive ("HSI") and blade vortex interaction ("BVI") noise in a rotor aircraft, such as a helicopter, is disclosed. The system comprises a plurality of rotor blades extending radially in spaced relationship from a central hub, each of the blades having spaced apart upper and lower surfaces, an interior volume between the surfaces, and leading and trailing edges at the respective joined edges of the upper and lower surfaces. Air intake passages are disposed on the surfaces of each blade proximate the leading edge to controllably admit air into the interior volume; and air output passages are disposed on the surfaces of each blade proximate the trailing edge and the outer edge tip to controllably expel air from the interior volume of the blade. Admitting and expelling of air into and out of the interior volume of each blade is controlled in accordance with a determined condition of that blade. When the presence of BVI or HSI noise, or any condition giving rise to such noise, is sensed, the admittance and expulsion of air is activated to minimize the noise.

대표청구항 ▼

[ What is claimed:] [1.]1. A system for reducing high speed impulsive blade noise (HSI) in aircraft rotors, the system comprising:a plurality of rotor blades extending radially in spaced relationship from a central hub, each of said blades having spaced apart upper and lower surfaces, an interior vo

[ What is claimed:] [1.]1. A system for reducing high speed impulsive blade noise (HSI) in aircraft rotors, the system comprising:a plurality of rotor blades extending radially in spaced relationship from a central hub, each of said blades having spaced apart upper and lower surfaces, an interior volume between said surfaces, and leading and trailing edge portions at respective opposing joined edges of said upper and lower surfaces of each blade;air intake passages disposed on the upper and lower surfaces of each blade proximate the leading edge and tip edge to controllably admit air into said interior volume;air output passages disposed on the upper and lower surfaces of each blade proximate the trailing edge and tip edge to controllably expel air from said interior volume; andmeans for controlling said admitting and expelling of air into and out of the interior volume of each blade in accordance with a determined condition of each blade during its rotation,wherein said controlling means includes sound sensors mounted off the blades for determining high speed impulse noise produced by said rotating blades and controlling admitting or expelling of air through said passages in accordance therewith.