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morphing RAO-flap

IP.com Disclosure Number: IPCOM000240242D
Publication Date: 2015-Jan-15
Document File: 4 page(s) / 231K

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The IP.com Prior Art Database

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09970: IP.COM

Abstract

Abstract morphing RAO-flap It is an idea to replace the rigid ram air outlet flap (RAO-flap) by a morphing flap, which is aerodynamically optimized, leading to less drag and to reduced loads on the flap. By adapting/changing the shape of the RAO flap when changing the opening position, the flow around the flap will be more favorable.

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Abstract morphing RAO-flap

It is an idea to replace the rigid ram air outlet flap (RAO-flap) by a morphing flap, which is aerodynamically optimized, leading to less drag and to reduced loads on the flap. By adapting/changing the shape of the RAO flap when changing the opening position, the flow around the flap will be more favorable.

Morphing RAO-flap

Bleed air may be used for the pressurization of the air cabin. The cooling of the hot bleed air is done by the outer flow, entering the ram air cooling channel through an intake. As the cooling demand is changing during the aircraft mission, the intake and outlet has to be adjusted accordingly.

To ensure a requested cooling ram air flow, the height of the intake and exhaust may be adjustable. The adjustment of the exhaust area can be done by moving a rigidly formed and hinged flap (Fig.1 & 2), which is driven by an actuator.

At an open position of the exhaust flap, the outer free stream is strongly diverted by the flap, possibly leading to high loads (static and dynamic loads, e.g. vibrations) on the flap and an increase of the aircraft drag (see Fig. 3).

It is an idea to replace the rigid RAO flap by a morphing flap, which is aerodynamically optimized, leading to less drag and to reduced loads on the flap. By adapting/changing the shape of the RAO flap when changing the opening position, the flow around the flap will be more favorable, inducing less drag.

The benefit of a morphing flap would be:

1. A smoother flow path, avoiding a sharp deflection of the flow. This leads to a reduction of the drag induced by the deflected flap and less losses of the hot jet leaving the cooling channel (higher performance of the channel)...