Aircraft Engine Seal Thermal Barrier for Fire-Resistant Fluid Joints
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing fire protection structures for aircraft engine seals fail to adequately protect elastomeric seals from excessive heat, leading to potential leakage of flammable fluids during engine fires, which poses a serious fire hazard.
Innovation Solution
Implementing thermal barriers with annular cavities filled with thermal insulation media on both sides of the sealing ring to break thermal conduction paths, using materials like stainless steel or aluminum for the transfer tube and integrating sleeves for creating air gaps to shield the seals from heat transfer from the engine case and the flammable fluid.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If existing fire protection structures are used, then the structure is simple, but the seals are not adequately protected from excessive heat leading to potential leakage
Solution Approach 1:
The patent introduces thermal insulation media (such as aerogels, foams, or air gaps) as intermediary substances between the fire-exposed components and the elastomeric seals. These intermediaries act as thermal barriers that mediate the heat transfer process, protecting the seals from excessive temperatures while maintaining the overall structural integrity and functionality of the fluid containment system.
Solution Approach 2:
The thermal insulation media are integrated within the existing structural components of the fluid containment system. The insulation materials are nested within cavities, walls, or gaps of the existing structure, allowing the thermal protection function to be embedded within the mechanical structure without adding significant external complexity.
2Reliability
If thermal barriers are added to protect seals, then seal protection is improved, but device complexity increases
Solution Approach 1:
The thermal insulation media serve multiple functions simultaneously: they provide thermal protection to the seals, maintain structural integrity during fire exposure, and can be integrated with existing structural components. This multi-functionality reduces the need for separate dedicated protection systems, thereby limiting the increase in device complexity.
Solution Approach 2:
The thermal protection is applied locally at critical interfaces where elastomeric seals are most vulnerable to heat exposure. Rather than protecting the entire fluid containment system uniformly, the thermal barriers are strategically positioned at specific locations where seals contact hot surfaces or flammable fluids, optimizing protection effectiveness while minimizing added complexity.
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 thermal barriers effectively delay the rise in temperature at the seals, preventing seal degradation and potential leakage, ensuring the seals remain functional during a fire event, thus meeting airworthiness certification standards.
Implementation Method 1
a first thermal barrier configured to reduce a flow of thermal energy from the gearbox or the transfer tube to the sealing ring, the first thermal barrier including a first annular cavity filled with a first thermal insulation medium
Data Source
AI summary
An aircraft engine has a flammable fluid containment assembly including a component containing a flammable fluid. A transfer tube is fluidly connected to the component. A sealing ring is provided at an interface between the aircraft engine component and the transfer tube. A first thermal barrier is provided between the sealing ring and a first one of the aircraft engine component and the flammable fluid inside the transfer tube. The first thermal barrier includes a first annular cavity filled with a first thermal insulation medium and axially spanning the sealing ring.