Morphing Airfoil Leading Edge Shape Control Mechanism

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Conventional aircraft leading edge devices disrupt airflow, causing laminar flow to transition to non-laminar flow, reducing aerodynamic performance, generating noise, and leading to vibration and flutter, especially during cruise phases of flight.

Innovation Solution

A morphing airfoil system with a flexible leading edge skin and a shape control mechanism that transitions between different curvature profiles without changing the arc length, eliminating steps and gaps to maintain laminar flow and reduce noise and vibration.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Productivity

If conventional leading edge devices are deployed, then aerodynamic performance is improved during takeoff and landing, but geometric features such as steps and gaps disrupt laminar flow and generate noise during cruise

Engineering Contradiction:
Improveaerodynamic performanceVSAvoidflow disruption and noise
Core Design Contradiction:
ProductivityVSObject-generated harmful factors

Solution Approach 1:

The leading edge device is designed to be movable between deployed and retracted positions. When deployed, it provides high-lift characteristics for takeoff and landing. When retracted, it becomes flush with the wing surface, eliminating steps and gaps that disrupt laminar flow. This dynamic configuration allows the device to adapt to different flight phases, resolving the contradiction between improving aerodynamic performance and minimizing flow disruption.

Inventive Principle:
Principle #15Dynamics

Solution Approach 2:

The leading edge device incorporates a thin-film or flexible skin that can conform to the wing surface when retracted, creating a smooth transition without geometric discontinuities. This flexible construction allows the device to eliminate steps and gaps that would otherwise disrupt laminar flow and generate noise during cruise, while still providing the necessary structural integrity when deployed.

Inventive Principle:
Principle #30Flexible shells and thin films

2Productivity

If leading edge devices with steps and gaps are used, then aerodynamic performance is enhanced during high-angle-of-attack phases, but laminar flow transitions to non-laminar flow reducing overall performance

Engineering Contradiction:
Improveaerodynamic performance at high angle of attackVSAvoidlaminar flow maintenance
Core Design Contradiction:
ProductivityVSReliability

Solution Approach 1:

The device transitions between a deployed state that enhances high-angle-of-attack performance and a retracted state that maintains laminar flow. During cruise, the retracted position eliminates geometric features that would trigger early transition to non-laminar flow, thereby maintaining reliable laminar flow conditions over the wing surface.

Inventive Principle:
Principle #15Dynamics

3Productivity

If conventional leading edge devices are deployed, then low-speed performance is improved, but vibration and flutter occur affecting actuating mechanisms

Engineering Contradiction:
Improvelow-speed performanceVSAvoidactuating mechanism stability
Core Design Contradiction:
ProductivityVSReliability

Solution Approach 1:

The flexible skin or thin-film construction of the leading edge device reduces structural rigidity that would otherwise cause vibration and flutter at certain frequencies. This flexible design dampens oscillations and reduces the transmission of vibratory forces to the actuating mechanisms, thereby improving the reliability and stability of the actuation system while still providing effective low-speed performance enhancement when deployed.

Inventive Principle:
Principle #30Flexible shells and thin films

Data Source

PatentEP2915741B1Morphing airfoil leading edge
Publication Date: 2019.02.20 THE BOEING CO
  • EP2915741B1 patent drawingFigure 1
  • EP2915741B1 patent drawingFigure 2~3
  • EP2915741B1 patent drawingFigure 4~5

AI summary

An airfoil may include a leading edge 200 and a shape control mechanism 400. The leading edge may include a flexible leading edge skin 214 having a first end 216, a second end 218, and an arc length defined therebetween. The shape control mechanism may be attached to the flexible leading edge skin at a plurality of support locations 224 and may transition the flexible leading edge skin from a first shape 228 having a first curvature profile 230 to a second shape 232 having a second curvature profile 234 different than the first curvature profile without a change in the arc length.