Thrust Reverser Blocker Door Load Path Segmentation

Solution Overview

Problem

Gas turbine engine thrust reverser assemblies require a larger, heavier actuation system to manage high pressure airflow, which increases weight and space consumption.

Innovation Solution

A blocker door mechanism with a stop structure that shares aerodynamic loading between the nacelle and core engine, reducing the load on the actuation system by distributing it through separate load paths.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Strength

If a larger actuation system is used to accommodate high pressure airflow against the blocker door, then the thrust reverser can withstand the aerodynamic loading, but the actuation system consumes additional space and adds weight to the engine

Engineering Contradiction:

Improveaerodynamic loading capacityVSAvoidactuation system weight

Core Design Contradiction:

StrengthVSWeight of moving object

Solution Approach 1:

The aerodynamic loading is segmented into two separate load paths: one transferring load to the nacelle and another transferring load to the core engine. This segmentation allows the actuation system to handle only a portion of the total load, reducing its required strength and weight while maintaining overall structural integrity

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The blocker door acts as an intermediary element that distributes aerodynamic loads to two different structural components (nacelle and core engine). By introducing this load-distributing intermediary, the actuation system no longer needs to independently withstand the full aerodynamic pressure, thereby reducing its size and weight

Inventive Principle:

Principle #24Intermediary (Mediator)

2Strength

If a larger actuation system is used to accommodate high pressure airflow against the blocker door, then the thrust reverser can withstand the aerodynamic loading, but the actuation system consumes additional space in the engine

Engineering Contradiction:

Improveaerodynamic loading capacityVSAvoidactuation system volume

Core Design Contradiction:

StrengthVSVolume of moving object

Solution Approach 1:

The aerodynamic loading is segmented into two separate load paths: one transferring load to the nacelle and another transferring load to the core engine. This segmentation allows the actuation system to handle only a portion of the total load, reducing its required strength and weight while maintaining overall structural integrity

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The blocker door acts as an intermediary element that distributes aerodynamic loads to two different structural components (nacelle and core engine). By introducing this load-distributing intermediary, the actuation system no longer needs to independently withstand the full aerodynamic pressure, thereby reducing its size and weight

Inventive Principle:

Principle #24Intermediary (Mediator)

Data Source

PatentUS10851734B2Thrust reverser assembly

Publication Date: 2020.12.01 STE MRAS LLC

AI summary

A thrust reverser assembly for high-bypass turbofan engine. The thrust reverser assembly includes a translating cowl mounted to a nacelle of an engine. The thrust reverser assembly includes blocker doors axially guided adjacent first ends thereof by a fixed structure and pivotally and slidably connected along lengths thereof to an inner wall of the translating cowl so that translation of the translating cowl in the aft direction causes the blocker door to move from a stowed position to a deployed position. The thrust reverser assembly includes a stop disposed on the core engine or on the blocker door, receiving the load from the high pressure airflow, otherwise borne by an actuation system when deploying the translating cowl and blocker door.