Foldable Ram Air Inlet Filter for Aircraft ECS

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

The Environmental Control System (ECS) in aircraft is prone to failures due to clogged heat exchangers and particulate damage, leading to maintenance costs and flight disruptions, with no effective method to detect clogging from outside the aircraft.

Innovation Solution

A filtering assembly is integrated into the RAM air inlet system, featuring an upstream modulation panel and downstream air filter subassembly that can be actuated to move into and out of the air flow, ensuring comprehensive filtration and minimizing damage to heat exchangers by positioning the filter at the air outlet side to cover the entire duct cross-section.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Object-affected harmful factors

If a deflector door is used to prevent ice, slush, rocks and other unwanted material from entering the RAM air system, then protection against large particles is improved, but low weight particles such as dust, debris, catkins, and sands can still enter and clog the heat exchangers

Engineering Contradiction:
Improveprotection against large particlesVSAvoidclogging of heat exchangers
Core Design Contradiction:
Object-affected harmful factorsVSReliability

Solution Approach 1:

The filtration function is segmented into multiple stages: the deflector door handles large particles (ice, slush, rocks) while the newly added filter assembly handles fine particles (dust, debris, catkins, sands). This segmentation allows each component to specialize in a specific particle size range, solving the problem of fine particle clogging that the deflector door alone cannot prevent.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

A filter assembly is introduced as an intermediary component between the deflector door and the heat exchangers. This intermediary filter captures fine particles that pass through the deflector door, preventing them from reaching and clogging the heat exchangers, thus maintaining system reliability.

Inventive Principle:
Principle #24Intermediary (Mediator)

2Reliability

If the filter assembly is positioned at the air outlet side to cover the entire duct cross-section, then filtration effectiveness is improved, but the device complexity and space requirements increase

Engineering Contradiction:
Improvefiltration effectivenessVSAvoidfilter assembly structure
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The filter assembly is designed to perform multiple functions: it filters fine particles, structures the airflow, and can be integrated with existing modulation panel assemblies. By combining these functions into a single multi-functional component, the patent achieves high filtration effectiveness without proportionally increasing device complexity.

Inventive Principle:
Principle #6Universality (Multi-functionality)

Solution Approach 2:

The filter assembly is nested within or integrated with the existing modulation panel assembly structure. This nesting approach allows the filter to cover the entire duct cross-section for maximum filtration effectiveness while utilizing the space and structural framework already present in the RAM air inlet system, thereby minimizing additional complexity.

Inventive Principle:
Principle #7Nested doll (Nesting)

3Reliability

If scheduled maintenance is performed to inspect and clean heat exchangers, then clogging detection is possible, but flight delays and maintenance costs occur

Engineering Contradiction:
Improvedetection of cloggingVSAvoidmaintenance downtime
Core Design Contradiction:
ReliabilityVSLoss of time

Solution Approach 1:

The filter assembly performs preliminary action by capturing fine particles before they can reach and accumulate in the heat exchangers. This preventive filtration reduces the frequency and severity of clogging, thereby reducing the need for scheduled maintenance interventions and minimizing flight delays and maintenance costs.

Inventive Principle:
Principle #10Preliminary action

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 solution effectively reduces clogging and particulate damage to heat exchangers, preventing ECS failures and associated maintenance costs, while allowing for improved airflow management during various flight phases.

Implementation Method 1

an air filter subassembly downstream of the modulation panel subassembly. The air filter subassembly may be actuated to move into and out of the flow of inlet air

Methodology Applied
Scientific EffectPhysical filtration: Filter (physical)

Data Source

PatentEP3511247B1Foldable ram air inlet filter
Publication Date: 2023.06.14 HONEYWELL INTERNATIONAL INC
  • EP3511247B1 patent drawingFigure 1
  • EP3511247B1 patent drawingFigure 2
  • EP3511247B1 patent drawingFigure 3A

AI summary

A filtering assembly (200, 300) that receives an inlet air (206, 306) includes a modulation panel subassembly (205, 305), an air filter subassembly (202, 302) downstream of the modulation panel subassembly, wherein the air filter subassembly is configured to discharge the inlet air from the filtering assembly, and an arm subassembly (204, 304) configured to move the modulation panel subassembly and to move the air filter subassembly. The air filter subassembly moves into and out of a flow of the inlet air.