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Method for inhibiting blade-vortex interference noises of helicopter

A vortex interference, helicopter technology, applied in the field of helicopter rotor blades, to achieve the effect of simple structure, low manufacturing cost and convenient maintenance

Active Publication Date: 2018-06-29
XIAMEN UNIV
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  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0006] The object of the present invention is to provide a kind of method for suppressing helicopter propeller-vortex interference noise utilizing synthetic jet technology for the above-mentioned deficiency that existing suppressing helicopter rotor blade-vortex interference noise exists

Method used

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  • Method for inhibiting blade-vortex interference noises of helicopter
  • Method for inhibiting blade-vortex interference noises of helicopter
  • Method for inhibiting blade-vortex interference noises of helicopter

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Experimental program
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Embodiment Construction

[0020] Such as figure 1 and 2 As shown, when the helicopter is flying forward, the rotor rotates at an angular velocity ω, and the airflow with velocity V flows through the tip of the forward blade, forming a pressure difference between the upper and lower surfaces of the tip, and the pressure on the upper surface is P 1 , the pressure on the lower surface is P 2 , and P 1 2 . Under the action of this pressure gradient, the gas on the lower surface will roll up and flow around the tip of the paddle, forming a figure 1 and figure 2 An upturned tip vortex Г 1 . its vortex axis l 1 It will be in contact with the subsequent blades, generating paddle-vortex interference noise.

[0021] Such as image 3 As shown, a synthetic jet generator G is installed at the tip of the helicopter blade. The generator G is buried inside the blade tip, its jet outlet is flush with the lower surface of the blade tip, and the direction of the jet flow is backward and downward relative to th...

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Abstract

The invention provides a method for inhibiting blade-vortex interference noises of a helicopter and relates to helicopter rotor wing blades. At least one synthetic jet generator is distributed at a position, which has a proper distance to an end face, of a blade tip; the synthetic jet generator is powered by a power supply; synthetic jet, which is backward and downward relative to the frontward movement direction of the rotor wing blade, is generated on the lower surface of the blade tip and is used for weakening blade tip vortex strength, and a falling direction of the blade tip is changed; acondition that the blade tip vortex and subsequent blades have mutual interference is avoided so that the effect of inhibiting the blade-vortex interference noises is realized. Structure parameters of the synthetic jet generator can be optimized according to specific actual requirements, and the jet strength also can be changed through adjusting loading electrical parameters of the synthetic jetgenerator; blade-vortex interference is initiatively and flexibly intelligently controlled; the method has the advantages of simple structure, low manufacturing cost, convenience for maintenance, no changes of an original aerodynamic shape of the rotor wing blade tip and the like.

Description

technical field [0001] The invention relates to a helicopter rotor blade, in particular to a method for suppressing helicopter blade-vortex interference noise by using synthetic jet technology. Background technique [0002] Helicopters have unique properties such as vertical take-off and landing, hovering, and low-altitude and low-speed flight, making them more and more used in national defense and civilian fields. However, helicopters also have the disadvantage of excessive noise, which reduces their invisibility in the military, easily exposes their whereabouts prematurely, and greatly affects the battlefield penetration and survivability of helicopters; in terms of civilian use, excessive noise not only affects The ride comfort of the occupants also causes serious noise pollution, which does not meet the environmental protection requirements. [0003] Helicopter noise mainly comes from the aerodynamic noise of the rotor, which is generated by the unsteady motion and flow...

Claims

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Application Information

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Patent Type & Authority Applications(China)
IPC IPC(8): B64C27/46B64C27/467
CPCB64C27/46B64C27/467
Inventor 林麒陈约适刘汝兵
Owner XIAMEN UNIV