Micro-blowing structure and method for resistance reducing and lift increasing of supercritical airfoil

Abstract

The invention discloses a micro-blowing structure and method for resistance reducing and lift increasing of a supercritical airfoil and belongs to the technical field of aircraft design. Skins with micro holes are arranged near the rear edge of the lower airfoil surface of the airfoil, micro-blowing is started under the cruising state, the wall face friction resistance in the micro-blowing actingarea is reduced remarkably, and the pressure difference resistance of the airfoil is further reduced through increasing of the pressure intensity in a micro-blowing upstream part, so that the total resistance of the airfoil is reduced; meanwhile, the lift of the airfoil can be increased through pressure intensity increasing caused by micro-blowing of the lower airfoil surface; and finally, the resistance reducing and lift increasing effects can be achieved simultaneously. The micro-blowing technique can be used in wide flowing fields including low-speed airliners, high subsonic speed airlinersand even supersonic aircrafts, and rapid development of manufacturing techniques in recent years provides a guarantee for application of the micro-blowing technique.

Description

technical field [0001] The invention belongs to the field of aircraft design, and in particular relates to a micro blowing structure and method for supercritical airfoil reducing drag and increasing lift. Background technique [0002] Micro-Blowing Technique (MBT) is a low-energy drag control technology developed to reduce the frictional resistance of the turbulent boundary layer on the surface of large passenger aircraft. This technology was proposed by Hwang of NASA Glenn Research Center in 1994. The microblowing technology opens a large number of micropores on the wall (such as figure 1 The typical microporous wall plate shown in ) blows air into the turbulent boundary layer near the wall through these micropores, so as to reduce the frictional resistance of the wall. The micro-blowing technology retains the drag reduction mechanism of the traditional air-blowing drag reduction technology for surface frictional resistance, and the frictional resistance of the microporous...

AI Technical Summary

Problems solved by technology

However, Hwang et al. applied the microblowing technology to the actual symmetrical airfoil in reference [1], which arranged the microporous skin at the chord length position of 11% to 66% of the upper and lower airfoils. The experimental measurement data It shows that under most of Hwang's experimental conditions, the micro-blowing technology causes the total drag to increase instead of decrease when applied to the airfoil

If this defect cannot be overcome, the micro-blowing technology cannot be applied to the actual large passenger aircraft.

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