Thrust Recovery Valve With Independent Flap Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional thrust recovery valves face challenges in high-resolution control at high differential pressures, aerodynamic torque issues, inefficient ram air ingress, high cost and weight, and complexity, which can lead to compromised safety and functionality in case of mechanical failure.
Innovation Solution
A thrust recovery valve design with two independently controlled flaps, where each flap is operated by its own actuator, allowing for higher resolution control, reduced torque requirements, and the ability to maintain functionality even if one door is mechanically stuck, thereby reducing weight, complexity, and cost while ensuring safe operation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Device complexity
If a single door valve is used with common drive mechanism, then weight and complexity are reduced, but control resolution deteriorates at high differential pressures
Solution Approach 1:
The valve is segmented into two independently controllable doors (first door and second door) instead of a single door. Each door can be positioned independently to achieve fine control resolution at high differential pressures while maintaining a relatively simple overall structure. The segmentation allows one door to handle coarse control while the other provides fine adjustment.
2Ease of operation
If a single door opens to 90 degrees, then ventilation function is achieved, but aerodynamic torque becomes very great
Solution Approach 1:
The ventilation function is divided between two doors that can open independently. The first door can open to a limited angle (less than 90 degrees) to reduce aerodynamic torque, while the second door provides additional opening. This segmentation allows the ventilation function to be achieved while each door experiences reduced aerodynamic forces compared to a single door opening fully.
3Weight of stationary object
If both doors are linked on a single valve, then weight is reduced, but reliability deteriorates when one door is mechanically stuck
Solution Approach 1:
The valve system is segmented into two independently actuated doors with separate control mechanisms. This segmentation ensures that if one door becomes mechanically stuck, the other door can still operate independently to maintain failsafe functionality. The independent actuation mechanisms prevent a single point of failure from compromising the entire system.
4Quantity of substance
If thrust recovery valve opens for negative pressure relief, then air exits fuselage, but ram air ingress benefit is lost
Solution Approach 1:
The air flow control is segmented between two doors that can be positioned independently. During negative pressure relief, the first door can be positioned to allow controlled air exit while the second door remains closed or partially closed to maintain the ram air scoop effect. This segmentation allows simultaneous achievement of pressure relief and energy recovery through selective door positioning.
Data Source
AI summary
A thrust recovery valve has two flaps, with each flap controlled independently via its own rotary actuator. Embodiments of the present invention also provide a cabin pressure control system that includes one or two thrust recovery valves and the controls architecture to efficiently operate the valves. On each thrust recovery valve, only one door can be operated during flight, making less effective area change per unit time (relative to the operating both doors at the same time), allowing higher resolution of valve control. Further, the valve doors can be made such that the primary door that is operated in flight is smaller than the other door (mostly only operated on the ground). Because the doors of the thrust recovery valve can be operated independently, the forward door of each valve can be rotated such that the door creates a ram air “scoop” to ingress air to prevent negative pressure from building up beyond a specified limit.