Duct assemblies for air management systems and methods of manufacture

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Solution Overview

Problem

Air management systems in pressurized aircraft face challenges in maintaining air cleanliness and preventing bacterial and dirt accumulation on filters, which can lead to reduced filtration efficiency and increased maintenance needs.

Innovation Solution

An ultraviolet light surface protection system for ducts is introduced, featuring a photoactivated metal oxide coating and a germicidal ultraviolet light source with a wavelength between 180 nm and 280 nm, which provides UV resistance, reflectivity, and antimicrobial properties.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If filters are used to scrub air for cleanliness, then air quality is improved, but bacterial and dirt accumulation on filters occurs leading to reduced filtration efficiency

Engineering Contradiction:
Improvefiltration efficiencyVSAvoidbacterial and dirt accumulation
Core Design Contradiction:
ReliabilityVSObject-generated harmful factors

Solution Approach 1:

The patent applies preliminary action by implementing a UV-C irradiation system that continuously sterilizes air and duct surfaces before contaminants can accumulate on filters. The system pre-treats the air stream and duct interior surfaces with germicidal UV light, preventing bacterial and viral contamination from building up on filter surfaces, thereby maintaining filtration efficiency over extended periods.

Inventive Principle:
Principle #10Preliminary action

Solution Approach 2:

The patent introduces an intermediary UV-C irradiation system between the air intake and filter components. This intermediary sterilization system acts as a mediator that eliminates pathogens in the air stream before they reach the filters, and also treats the duct surfaces to prevent biofilm formation, thus protecting the filters from contamination accumulation.

Inventive Principle:
Principle #24Intermediary (Mediator)

2Reliability

If duct materials are exposed to UV light for sterilization, then air sterilization is achieved, but UV degradation of duct materials occurs

Engineering Contradiction:
Improveair sterilizationVSAvoidUV degradation
Core Design Contradiction:
ReliabilityVSObject-affected harmful factors

Solution Approach 1:

The patent converts the harmful effect of UV light on duct materials into a beneficial outcome by applying a reflective coating to the duct interior surfaces. The coating reflects UV-C light away from the duct material, preventing degradation, while still allowing the UV light to effectively sterilize the air stream passing through the duct. The harmful UV exposure to duct materials is transformed into a controlled reflection pattern that maintains sterilization efficacy.

Inventive Principle:
Principle #22Blessing in disguise (Convert harm into benefit)

Solution Approach 2:

The patent employs a thin film reflective coating applied to the interior surfaces of the duct. This thin film acts as a protective barrier that allows UV-C light to pass through for air sterilization while reflecting the radiation away from the underlying duct material, preventing UV-induced degradation and extending the service life of the duct system.

Inventive Principle:
Principle #30Flexible shells and thin films

3Reliability

If germicidal UV light is emitted into the flow path, then air sterilization is improved, but maintenance requirements increase due to UV light source replacement

Engineering Contradiction:
Improveair sterilizationVSAvoidmaintenance requirements
Core Design Contradiction:
ReliabilityVSEase of repair

Solution Approach 1:

The patent implements self-service by designing the UV-C irradiation system with self-diagnostic and self-reporting capabilities. Sensors monitor the intensity and operational status of UV light sources, automatically detecting when bulbs require replacement. The system provides maintenance alerts and tracking, enabling proactive scheduling of bulb replacements before sterilization efficacy deteriorates, thereby reducing unexpected maintenance interruptions.

Inventive Principle:
Principle #25Self-service

Solution Approach 2:

The patent incorporates feedback mechanisms through UV intensity sensors and monitoring systems that continuously assess the performance of germicidal UV light sources. The system provides real-time feedback on sterilization efficacy and automatically alerts operators when maintenance is required, optimizing the maintenance schedule based on actual performance data rather than fixed time intervals.

Inventive Principle:
Principle #23Feedback

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 system effectively sterilizes air within the ducts, reduces microbial growth on surfaces, and enhances the durability of duct materials against UV degradation, thereby improving air quality and reducing maintenance requirements.

Implementation Method 1

a photoactivated metal oxide coating

Methodology Applied
Scientific EffectPhotoactivation: Photopolymerisation

Implementation Method 2

a photocatalytic antimicrobial coating

Methodology Applied
Scientific EffectPhotocatalysis: Catalysis

Implementation Method 3

a light source operable to emit a germicidal ultraviolet light into the flow path defined by the duct to sterilize the air

Methodology Applied
Scientific EffectGermicidal ultraviolet radiation: Radiation

Implementation Method 4

configured to be ultraviolet resistive, reflective, and anti-microbial

Methodology Applied
Scientific EffectReflection: Reflection

Implementation Method 5

a hydrophobicity layer

Methodology Applied
Scientific EffectHydrophobicity: Hydrophobe

Data Source

PatentEP3944869B1Duct assemblies for air management systems and methods of manufacture
Publication Date: 2025.04.02 GOODRICH CORP
  • EP3944869B1 patent drawingFigure 1
  • EP3944869B1 patent drawingFigure 2
  • EP3944869B1 patent drawingFigure 3

AI summary

An ultraviolet light surface protection system for a duct (24) may comprise an interior surface (56) of the duct; a light source (52) operable to emit a germicidal ultraviolet light into a flow path of the duct (24) defined by the interior surface of the duct to sterilize an air to be provided to a conditioned area; and a coating disposed on the interior surface (56), the coating configured to be ultraviolet resistive, reflective, and anti-microbial.