Integrated Variable Area Fan Nozzle and Thrust Reverser

Solution Overview

Problem

Conventional gas turbine engines lack integrated functionality that enhances propulsive efficiency and reduces complexity and weight, as their thrust reversers do not provide additional functionality beyond thrust reversal.

Innovation Solution

Integration of a variable area fan nozzle (VAFN) with a thrust reverser, utilizing a common actuation system, to control bypass flow and divert airflow for thrust reversal, with a gear system and actuator mechanism that allows for multiple positions and apertures to optimize bypass flow communication.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Adaptability or versatility

If a conventional thrust reverser is used, then thrust reversal function is achieved, but additional functionality is not provided and complexity remains high

Engineering Contradiction:

Improveadditional functionalityVSAvoidcomplexity

Core Design Contradiction:

Adaptability or versatilityVSDevice complexity

Solution Approach 1:

The thrust reverser cascades are designed to perform multiple functions: serving as thrust reversal surfaces when deployed, and acting as variable area fan nozzle elements when in the stowed position. This multi-functionality allows the same structural components to provide both thrust reversal capability and propulsive efficiency enhancement through bypass flow control, thereby adding functionality without proportionally increasing device complexity

Inventive Principle:

Principle #6Universality (Multi-functionality)

2Adaptability or versatility

If separate VAFN and thrust reverser systems are used, then both functions are achieved, but weight and complexity increase

Engineering Contradiction:

ImprovefunctionalityVSAvoidweight

Core Design Contradiction:

Adaptability or versatilityVSWeight of moving object

Solution Approach 1:

The patent merges the VAFN system and thrust reverser system into a single integrated mechanism. The thrust reverser cascades structure serves dual purposes: as thrust reversal surfaces when deployed, and as VAFN elements that control bypass flow when in the stowed position. This consolidation eliminates the need for separate structural components and actuation systems, thereby reducing overall weight while maintaining both functions

Inventive Principle:

Principle #5Merging (Combining)

3Productivity

If conventional thrust reverser design is used, then thrust reversal is achieved, but propulsive efficiency is not enhanced

Engineering Contradiction:

Improvepropulsive efficiencyVSAvoidcomplexity

Core Design Contradiction:

ProductivityVSDevice complexity

Solution Approach 1:

The thrust reverser cascades are designed to perform multiple functions: serving as thrust reversal surfaces when deployed, and acting as variable area fan nozzle elements when in the stowed position. This multi-functionality allows the same structural components to provide both thrust reversal capability and propulsive efficiency enhancement through bypass flow control, thereby adding functionality without proportionally increasing device complexity

Inventive Principle:

Principle #6Universality (Multi-functionality)

Data Source

PatentUS11499502B2Dual function cascade integrated variable area fan nozzle and thrust reverser

Publication Date: 2022.11.15 RTX CORP

AI summary

A gas turbine engine system according to an exemplary aspect of the present disclosure may include a core engine defined about an axis, a fan driven by the core engine about the axis to generate bypass flow, and at least one integrated mechanism in communication with the bypass flow. The at least one integrated mechanism includes a variable area fan nozzle (VAFN) and thrust reverser, and a plurality of positions to control bypass flow.