Leading-Edge Flap Kinematics for Gap Optimization
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Common kinematics for extending leading-edge slats, such as Krüger flaps, often result in a straightforward motion that does not optimize the gap between the flap and the wing, leading to suboptimal airflow and potential flow separation during deployment.
Innovation Solution
A flap system comprising a leading-edge flap, an actuator, and a complex arrangement of fixed and connecting links, including an auxiliary link, which allows for a more complex motion that adjusts the angle between the flap and the wing chord, maintaining a small gap and preventing flow separation by transitioning from a retracted to an extended position.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Device complexity
If a simple rotary motion mechanism is used for the Krüger flap, then the system complexity is reduced, but the gap between the flap and wing leading edge cannot be optimized, leading to flow separation
Solution Approach 1:
The patent applies dynamics by transitioning from a simple rotary motion to a more complex motion path that dynamically adjusts the flap position. The flap follows a specific trajectory that maintains an optimized gap between the trailing edge and wing leading edge throughout deployment, preventing flow separation while achieving the desired aerodynamic angles. This dynamic motion path resolves the contradiction by accepting increased mechanism complexity to ensure airflow stability.
2Reliability
If a complex motion path is implemented to optimize the gap between flap and wing, then airflow performance is improved, but the mechanism complexity increases
Solution Approach 1:
The patent segments the flap deployment into distinct phases: initial rotation to achieve the aerodynamic angle, followed by a controlled translation along a defined path that maintains the optimized gap. This segmentation allows the complex motion to be achieved through a structured sequence of movements rather than a single complex mechanism, making the system more manageable while ensuring airflow stability.
Data Source
AI summary
A flap system driving a leading-edge flap between retracted and extended positions comprises a leading-edge flap, an actuator, first, second and third fixed links, first and second connecting links, and an auxiliary link. The first, second and third fixed links are rotatably supported on respective first, second and third structurally fixed points by respective first, second and third support joints. The first fixed link couples with an end of the first connecting link, which is coupled with a first flap joint at another end. The second fixed link rotatably couples with a central region of the first connecting link. The third fixed link rotatably couples with an end of the second connecting link, which is coupled with a second flap joint at another end. The second connecting link couples with the first fixed link through the auxiliary link, each at positions inside of the respective ends.