Variable Nozzle Helical Thread Alignment

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Conventional gas turbine engine cowl structures are prone to misalignment during operation, limiting their effectiveness and efficiency in modulating annular exhaust flow.

Innovation Solution

A variable nozzle apparatus with a moveable cowl portion threadably engaged on a static portion via helical threads, allowing circumferential rotation and axial translation to modulate the annular airflow, preventing misalignment and improving operational efficiency.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If conventional cowl structures are used for modulating annular exhaust flow, then the device complexity is reduced, but the reliability deteriorates due to misalignment during operation

Engineering Contradiction:
Improvealignment stabilityVSAvoidcowl structure
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The cowl structure is designed with movable portions that can dynamically adjust their position relative to the static portion, transitioning from a fixed configuration to a dynamically adjustable one. This allows the cowl to maintain proper alignment during operation while modulating the annular exhaust flow, resolving the contradiction between reliability and complexity by introducing controlled movement rather than rigid fixation

Inventive Principle:
Principle #15Dynamics

Solution Approach 2:

The cowl is divided into multiple portions - static portions and movable portions - that can independently position themselves. This segmentation allows each portion to be optimized for its specific function while maintaining overall alignment, preventing the misalignment issues that plague conventional unified cowl structures

Inventive Principle:
Principle #1Segmentation

2Reliability

If the cowl structure is made movable to prevent misalignment, then the reliability improves, but the device complexity increases

Engineering Contradiction:
Improvecowl alignmentVSAvoidcowl mechanism
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The cowl structure incorporates movable portions that can adjust their position dynamically during operation. This dynamic capability allows the cowl to maintain proper alignment and prevent misalignment issues, directly improving reliability while accepting the necessary increase in structural complexity to enable movement and adjustment

Inventive Principle:
Principle #15Dynamics

Solution Approach 2:

The movable portions of the cowl are designed to automatically maintain proper alignment through their own movement capabilities, without requiring external intervention or complex control systems. This self-adjusting mechanism improves reliability by preventing misalignment while minimizing the overall system complexity

Inventive Principle:
Principle #25Self-service

Data Source

PatentEP3483416B1Variable nozzle apparatus
Publication Date: 2021.05.19 RTX CORP
  • EP3483416B1 patent drawingFigure 1
  • EP3483416B1 patent drawingFigure 2A~2B
  • EP3483416B1 patent drawingFigure 3

AI summary

A variable nozzle apparatus (100) may include a radially inward structure (110) and a radially outward structure (120) circumscribing the radially inward structure (110). An annular flow channel (115) is defined between the radially inward structure (110) and the radially outward structure (120). One of the radially inward structure (110) and the radially outward structure (120) includes a static portion (122) and a moveable portion (124). The moveable portion (124) may be to the static portion (122) via helical threads (125) and may thus configured to rotate circumferentially and translate axially relative to the static portion (122). Movement of the moveable portion (124) relative to the static portion (122) may change a radial dimension of the annular flow channel (115).