Double-Skin Nozzle Junctions with Leak Blocking and Drain Segmentation

Solution Overview

Problem

In double-skin nozzle systems used for transporting liquids in aircraft, contamination of the external tube occurs when a seal between internal and external tubes becomes defective, leading to lengthy maintenance as the entire system needs to be cleaned to find the defective junction, as there is only one drain and the external tube becomes contaminated throughout its length.

Innovation Solution

The system incorporates at least two junction systems with blocking devices along the external tube to isolate and block liquid leaks from the internal tube, and multiple drains to isolate and remove the leaked liquid, allowing for swift identification and replacement of defective junctions without full system decontamination.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Device complexity

If a single drain is used in the external tube, then the structure is simple, but the contamination zone spreads throughout the entire external tube length when a leak occurs

Engineering Contradiction:

Improvedrain structureVSAvoidcontamination zone

Core Design Contradiction:

Device complexityVSObject-affected harmful factors

Solution Approach 1:

The external tube is divided into multiple segments or zones, each equipped with its own drain and blocking device. When a leak is detected in a specific zone, only that zone needs to be isolated and cleaned, rather than the entire external tube. This segmentation limits the contamination zone to the specific segment where the leak occurs.

Inventive Principle:

Principle #1Segmentation

2Reliability

If the entire external tube is cleaned to find a defective junction, then all potential contamination zones are addressed, but the maintenance time becomes very lengthy

Engineering Contradiction:

Improvecontamination detectionVSAvoidmaintenance time

Core Design Contradiction:

ReliabilityVSLoss of time

Solution Approach 1:

The external tube is divided into multiple segments or zones, each equipped with its own drain and blocking device. When a leak is detected in a specific zone, only that zone needs to be isolated and cleaned, rather than the entire external tube. This segmentation limits the contamination zone to the specific segment where the leak occurs.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

Blocking devices are introduced as intermediary elements between the internal and external tubes at each junction point. These blocking devices can be activated to prevent liquid from leaking from defective junctions into the external tube, or to isolate contaminated zones. This intermediary mechanism enables selective containment and reduces the scope of maintenance operations.

Inventive Principle:

Principle #24Intermediary (Mediator)

3Object-affected harmful factors

If blocking devices are installed at multiple junction systems, then liquid leaks can be isolated to specific zones, but the device complexity increases

Engineering Contradiction:

Improvecontamination zoneVSAvoidjunction system structure

Core Design Contradiction:

Object-affected harmful factorsVSDevice complexity

Solution Approach 1:

The external tube is divided into multiple segments or zones, each equipped with its own drain and blocking device. When a leak is detected in a specific zone, only that zone needs to be isolated and cleaned, rather than the entire external tube. This segmentation limits the contamination zone to the specific segment where the leak occurs.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

Blocking devices are introduced as intermediary elements between the internal and external tubes at each junction point. These blocking devices can be activated to prevent liquid from leaking from defective junctions into the external tube, or to isolate contaminated zones. This intermediary mechanism enables selective containment and reduces the scope of maintenance operations.

Inventive Principle:

Principle #24Intermediary (Mediator)

Data Source

PatentUS8893742B2Double-skin nozzle system, junction system between two tube portions, and aircraft provided with such a system

Publication Date: 2014.11.25 AIRBUS OPERATIONS (SAS)

AI summary

A double-skin nozzle system including an internal tube for transporting a liquid, formed by a plurality of tube portions connected to one another by removable junction systems, an external tube positioned around the internal tube and formed by a plurality of tube portions connected to one another by junction systems, wherein at least two junction systems each include a blocking device for blocking, along the external tube, the flow of a liquid coming from a leak from the internal tube, and at least one drain for removing the liquid coming from the leak from the internal tube.