Thrust Reverser Sealing Membrane for Movable-Cascade Flow Deflection
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing thrust reversers with moving grids in aircraft propulsion systems suffer from aerodynamic disturbances and the inability to install acoustic panels due to recesses and flaps, and existing shutter membrane solutions are not suitable for moving-grid inverters, lacking ease of implementation and deployment reliability.
Innovation Solution
A thrust reverser design incorporating sealing membranes that deflect secondary flow towards deflection grids, guided by flexible attachment means and supported by guide means, ensuring smooth deployment and high aerodynamic and acoustic performance.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of operation
If recesses and flaps are provided in the radially inner wall for shutter deployment, then shutters can be accommodated in retracted position, but aerodynamic disturbances occur in the secondary flow and acoustic panel installation is prevented
Solution Approach 1:
The patent replaces rigid shutters with flexible membranes that can be stored within the radially inner wall without creating recesses. These thin film structures deflect the secondary flow when deployed and return to a compact state when retracted, eliminating aerodynamic disturbances while maintaining acoustic panel installation capability.
Solution Approach 2:
The invention transitions from static shutter structures to dynamic flexible membranes that adapt their configuration based on operational requirements. The membranes can be deployed to deflect flow when needed and retracted to a streamlined state during normal operation, providing dynamic flow control without permanent structural interruptions.
2Object-affected harmful factors
If rigid shutters are used in fixed-grid inverters, then flow diversion is achieved, but the solution is not suitable for moving-grid inverters and lacks deployment reliability
Solution Approach 1:
The patent employs flexible membranes instead of rigid shutters, allowing the flow diversion structure to adapt to the moving-grid configuration. These membranes can be reliably deployed and stowed without the mechanical complexity of rigid shutter mechanisms, ensuring consistent performance in moving-grid inverters.
Solution Approach 2:
The invention replaces complex mechanical shutter systems with simpler flexible membrane structures that rely on aerodynamic forces and elastic deformation for deployment and retraction. This substitution eliminates mechanical wear and complexity, improving reliability while maintaining flow diversion capability.
3Length of moving object
If moving grids are used instead of fixed grids, then nacelle length and mass are reduced, but shutter deployment complexity increases
Solution Approach 1:
The patent uses flexible membranes that can be integrated into the compact moving-grid structure without requiring additional deployment space. These membranes conform to the reduced nacelle geometry and can be deployed/retracted using simple mechanisms, maintaining the benefits of grid mobility while simplifying the flow control system.
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 design provides ease of deployment, high reliability, and improved aerodynamic and acoustic performance by using sealing membranes that extend along deflection grids, reducing aerodynamic disturbances and enabling acoustic panel installation.
Implementation Method 1
at least one sealing membrane designed to deflect at least a portion of the secondary flow towards said at least one set of deflection grids
Data Source
Figure 1~2
Figure 3
Figure 4
AI summary
The invention relates to a thrust reverser (30) for an aircraft propulsion assembly, comprising at least one sealing membrane (58) designed to deflect at least one portion of the secondary flow towards a set of cascades (32') when the movable structure (29) of the reverser is in the retracted thrust reversal position, the reverser also comprising: - first flexible hook means (59, 59a) connecting a first end of the membrane (58a) to the fixed structure (31) of the reverser, - second hook means (62, 70) connecting a second end (58b) of the membrane to the fixed structure (31) or to the movable structure (29), the second hook means being fixed to the radially inner delimiting wall (18) of the secondary vein (21B), or guided by internal guiding means fixed to the same radially inner delimiting wall (18).