Reverse Flow Relief Valve for Aircraft Bleed Air Systems
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In aircraft bleed air systems, reverse flow of pressurized air from downstream to upstream can occur during fault conditions, damaging engine operation when downstream pressure exceeds upstream pressure, and existing valve technologies fail to effectively prevent this reverse flow.
Innovation Solution
A reverse flow relief valve system that compares upstream and downstream pressures, creating a fluid communication path between servo pressure and ambient pressure to depressure the servo and close the bleed valve when downstream pressure exceeds upstream pressure, utilizing high-temperature resistant ceramic and metal components to prevent leakage and ensure reliable operation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Temperature
If traditional seals are used in the valve, then sealing function is provided, but they fail at high temperatures
Solution Approach 1:
The patent replaces traditional mechanical seals with a contactless magnetic field interaction system. The floating piston is actuated by magnetic forces from magnets positioned in the valve body, eliminating the need for physical seal contacts that fail at high temperatures. This substitution of mechanical sealing with magnetic actuation resolves the temperature reliability contradiction.
Solution Approach 2:
The patent changes the material parameters of the floating piston by using magnetically responsive materials that can operate reliably at high temperatures. The floating piston is designed with specific magnetic properties and thermal characteristics that allow it to respond to magnetic actuation while maintaining structural integrity and operational reliability in high-temperature environments where traditional seals would fail.
2Reliability
If the valve uses a complex sealing system to prevent leakage, then sealing is improved, but device complexity increases
Solution Approach 1:
The patent eliminates complex mechanical sealing systems by replacing them with a magnetic actuation mechanism. The floating piston is controlled by magnetic fields from permanently magnetized components in the valve body, creating a sealless design that prevents leakage without requiring complex seal arrangements. This substitution reduces device complexity while maintaining or improving sealing reliability.
Solution Approach 2:
The patent extracts and removes traditional seal components from the valve system, replacing them with a magnetic field-based actuation and sealing mechanism. By taking out the problematic sealing elements and using magnetic forces to control the floating piston position, the design achieves leakage prevention through a simpler, more reliable magnetic interaction system rather than complex mechanical seals.
3Productivity
If the bleed valve remains open to maintain flow, then system productivity is maintained, but reverse flow into the engine occurs during fault conditions
Solution Approach 1:
The patent incorporates a check valve mechanism that provides feedback control to prevent reverse flow. The check valve is positioned to automatically respond to pressure differential changes, closing to block reverse flow when downstream pressure exceeds upstream pressure, while allowing normal forward flow during operational conditions. This feedback mechanism protects the engine from reverse flow damage without compromising system productivity during normal operation.
Solution Approach 2:
The patent implements preliminary protective action by designing the check valve to preemptively block reverse flow paths before harmful reverse flow can reach the engine. The check valve is strategically positioned in the flow path to create a preliminary barrier that activates automatically when reverse pressure conditions develop, preventing the harmful effect before it can affect the engine, while maintaining full productivity during normal forward flow conditions.
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
Effectively prevents reverse flow into the engine by closing the bleed valve during fault conditions, ensuring safe engine operation and maintaining system integrity even at high temperatures without relying on temperature-intolerant seals.
Implementation Method 1
the ball is actuated axially between a first position and a second position based on the relative pressures provided at the first inlet and the second inlet
Implementation Method 2
the poppet member forms a seal with the second member when the ball is in a first position
Implementation Method 3
provides a fluid communication path between the third inlet and the fourth inlet via the interior chamber of the second stationary member when the ball is in a second position
Data Source
Figure 1
Figure 2A~2B
AI summary
A bleed valve system (10) includes a bleed valve (14), a valve regulator (18), a valve actuator (16) and a reverse flow relief valve (12). The bleed valve (14) is opened and closed to control a flow of bleed air from an upstream inlet (22) to a downstream outlet (24). The valve regulator (16) provides a servo pressure used to regulate the position of the bleed valve (14), and the valve actuator (18) is mechanically connected to open/close the bleed valve (14) based on the servo pressure provided by the valve regulator (18). The reverse flow relief valve (12) compares a pressure upstream of the bleed valve (14) to a pressure downstream of the bleed valve (14) and in response to the downstream pressure exceeding the upstream pressure creates a fluid communication path between the servo pressure and an ambient pressure to decrease the servo pressure such that the bleed valve (14) is closed.