Thrust Reverser Cascade Flow Deflection Shelf Integration

Solution Overview

Problem

Existing thrust reverser cascade assemblies for turbofan aircraft engines are inefficient due to the ancillary role of aft cascade rings, which add weight and length without directly contributing to air-turning functionality, necessitating an improved design that integrates structural support with air deflection.

Innovation Solution

The introduction of a flow deflection shelf with a forwardly extending deflector portion and an upstanding wall that removably attaches to an aft cascade ring, redirecting fan airflow and providing structural support to reduce the overall length and weight of the cascade assembly.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Stability of the object's composition

If an aft cascade ring is added to provide structural support, then the cascade assembly gains structural stability, but the overall weight and length of the assembly increase

Engineering Contradiction:

Improvestructural stabilityVSAvoidassembly weight

Core Design Contradiction:

Stability of the object's compositionVSWeight of moving object

Solution Approach 1:

The patent combines the structural support function and air deflection function into a single integrated flow deflection shelf component. The shelf includes a support portion that attaches to the cascade segment and a deflector portion that redirects airflow, eliminating the need for a separate aft cascade ring and reducing overall assembly weight and length.

Inventive Principle:

Principle #5Merging (Combining)

Solution Approach 2:

The flow deflection shelf performs multiple functions simultaneously: it provides structural support for the cascade segment, defines the rear boundary of the cascade assembly, and actively participates in redirecting airflow forward. This multi-functionality replaces the ancillary role of traditional aft cascade rings.

Inventive Principle:

Principle #6Universality (Multi-functionality)

2Stability of the object's composition

If an aft cascade ring is added to provide structural support, then the cascade assembly gains structural stability, but the overall length of the assembly increases

Engineering Contradiction:

Improvestructural stabilityVSAvoidassembly length

Core Design Contradiction:

Stability of the object's compositionVSLength of moving object

Solution Approach 1:

The patent combines the structural support function and air deflection function into a single integrated flow deflection shelf component. The shelf includes a support portion that attaches to the cascade segment and a deflector portion that redirects airflow, eliminating the need for a separate aft cascade ring and reducing overall assembly weight and length.

Inventive Principle:

Principle #5Merging (Combining)

3Productivity

If a separate flow deflection component is added to improve air-turning functionality, then the aerodynamic efficiency improves, but the device complexity increases

Engineering Contradiction:

Improveaerodynamic efficiencyVSAvoiddevice complexity

Core Design Contradiction:

ProductivityVSDevice complexity

Solution Approach 1:

The patent combines the structural support function and air deflection function into a single integrated flow deflection shelf component. The shelf includes a support portion that attaches to the cascade segment and a deflector portion that redirects airflow, eliminating the need for a separate aft cascade ring and reducing overall assembly weight and length.

Inventive Principle:

Principle #5Merging (Combining)

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

This configuration enhances the air-turning functionality of the thrust reverser while minimizing weight and length, improving the efficiency and aerodynamics of the thrust reverser system by integrating structural support directly into the air deflection mechanism.

Implementation Method 1

a flow deflection shelf that forms a rear or aft end of the cascade segment and removably attaches to an aft cascade ring. The deflector portion of each flow deflection shelf is configured to at least partially redirect, in the forward direction, at least a portion of the volume of fan air flow

Methodology Applied

Scientific EffectFlow deflection:

Data Source

PatentEP2581593B1Thrust reverser cascade assembly with flow deflection shelf

Publication Date: 2020.05.06 ROHR INC

Figure 1A~1B
Figure 1C~1D
Figure 1E

AI summary

An aircraft engine thrust reverser cascade assembly (100) includes a plurality of circumferentially spaced cascade segments (102), each cascade segment (102) including a plurality of spaced vanes (105), including an aft-most vane (107), and rails (104) defining a series of cells or air passages (106) therebetween. The cascade assembly (100) also includes an aft cascade ring (120) removably attached to the aft ends of the cascade segments (102). A flow deflection shelf (110) is mounted to each of the cascade segments (102) and includes a deflector portion (18) that at least partially extends forward of a group of cells (114) of the cascade segments (102) along which the flow deflection shelf (110) is mounted. The deflector portion (18) is configured to at least partially redirect at least a portion of a volume of air forwardly as the air outwardly passes through the group of cells (106) of the cascade segments (102).