Aircraft Vortex Generator with Deformable Flap for Tail Drag Reduction
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Solution Overview
Problem
Aircraft vertical tail planes and rudders generate excessive aerodynamic drag due to unused yawing moment capacity, leading to increased fuel consumption and reduced range, as they are sized for maximum yawing moment requirements that are never met under regular conditions.
Innovation Solution
Aircraft airflow modification devices with resiliently deformable flap members and base members that can change state from unbuckled to buckled configurations, allowing for adjustable vortex generation to improve airflow over the tail plane and rudder without increasing size, and featuring a simplified design with few moving parts to reduce maintenance and drag.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the vertical tail plane and rudder are sized to provide maximum yawing moment capacity, then the directional stability and control capability are improved, but the aerodynamic drag and fuel consumption increase due to unused capacity under regular operating conditions
Solution Approach 1:
The patent applies dynamics by making the vortex generator arrangement movable between extended and retracted positions through an actuator system. The arrangement transitions from a static to a dynamic configuration, allowing it to adapt to different operating conditions. During takeoff and landing, the vortex generator is extended to provide enhanced airflow control and reduce drag, while during cruise operations it is retracted to minimize parasitic drag, thus resolving the contradiction between maintaining control capability and reducing energy loss.
Solution Approach 2:
The patent changes the physical state and position parameters of the vortex generator arrangement. By altering the position parameter (extended vs. retracted) and the aerodynamic characteristics parameter (vortex generation capability), the system optimizes performance for different flight regimes. This parameter change allows the same structural component to serve multiple functions without requiring separate systems for each operating condition, thereby reducing overall drag while maintaining control capability when needed.
2Reliability
If the rudder deflection angle is increased to generate more yawing moment, then the control capability is improved, but the risk of stalling the flow at the rudder increases
Solution Approach 1:
The patent applies preliminary action by positioning the vortex generator forward of the rudder and extending it during takeoff and landing phases to pre-condition the airflow. The vortex generator creates controlled vortices that energize the boundary layer and delay flow separation before the airflow reaches the rudder. This preliminary airflow modification allows the rudder to operate at higher deflection angles without causing flow stalling, as the airflow remains attached and controlled through the vortex generation effect.
Solution Approach 2:
The vortex generator acts as an intermediary element between the freestream airflow and the rudder surface. It modifies the airflow characteristics in the intermediate region, creating a more favorable flow state that reduces the likelihood of stalling at the rudder. The vortex generator serves as a mediator that decouples the direct relationship between rudder deflection and flow separation, allowing greater control authority without proportional increases in stall risk.
3Reliability
If the vertical tail plane dimensions are increased to provide sufficient yawing moment, then the control capability is improved, but the device complexity and weight increase
Solution Approach 1:
The patent applies segmentation by dividing the airflow modification function into separate components: the vortex generator arrangement and the vertical tail plane/rudder system. Instead of increasing the entire vertical tail plane assembly to provide sufficient yawing moment, the invention segments the function by adding a dedicated vortex generator that creates beneficial vortices to enhance airflow control. This segmentation allows the main tail plane structure to remain smaller while the vortex generator provides the additional aerodynamic effectiveness needed for control capability.
Solution Approach 2:
The vortex generator serves as an intermediary device that enhances the aerodynamic effectiveness of the vertical tail plane without requiring increases in its physical dimensions. By placing the vortex generator in a strategic position forward of the rudder, it mediates the airflow to create more efficient vortex generation that enhances yawing moment capability. This intermediary approach allows the system to achieve better control performance with a smaller, less complex vertical tail plane structure.
4Adaptability or versatility
If a traditional vortex generator arrangement with multiple moving parts is used, then the airflow modification capability is improved, but the maintenance complexity and failure risk increase
Solution Approach 1:
The patent applies the taking out principle by extracting and removing complex mechanical components from the vortex generator arrangement. Instead of using traditional movable vortex generators with multiple joints, bearings, and actuation mechanisms, the invention extracts these complex parts and replaces them with a simpler, more reliable design. The vortex generator uses a flexible wing-like structure that can be positioned using a single actuator, eliminating the need for multiple moving parts and reducing maintenance requirements while preserving airflow modification capability.
Solution Approach 2:
The patent employs a simplified vortex generator design that prioritizes reliability and ease of maintenance over complex mechanical sophistication. The flexible wing structure and minimal actuation system represent a move toward a simpler, more robust configuration that is easier to maintain and less prone to failure. This approach accepts that the vortex generator will require periodic maintenance but designs it in a way that minimizes the complexity and cost of such maintenance, reducing overall system reliability risks.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The solution reduces aerodynamic drag by optimizing airflow, allowing for reduced size and weight of the vertical tail plane and rudder, improving fuel efficiency and range while minimizing maintenance complexity and costs.
Implementation Method 1
at least one resiliently deformable base member and at least one resiliently deformable flap member which extends from the resiliently deformable base member, wherein deformation of the resiliently deformable base member from a first state to a second state results in corresponding deformation of the resiliently deformable flap member from a first state to a second state
Implementation Method 2
A further object of the present technology is to provide a vortex generator arrangement that is less prone to failure or less costly to maintain by having few moving parts in its design
Data Source
AI summary
An aircraft airflow modification device, comprising: at least one resiliently deformable base member; and at least one resiliently deformable flap member that extends from the resiliently deformable base member. Deformation of the resiliently deformable base member from a first state to a second state results in corresponding deformation of the resiliently deformable flap member from a first state to a second state.