Open Rotor Fixed Guide Vanes for Swirl Loss Recovery

Solution Overview

Problem

Existing aircraft propulsion systems with variable geometry guide vanes/stators increase complexity and weight, outweighing the benefits of thrust recovery.

Innovation Solution

Implementing a fixed guide vane structure with manual adjustment capabilities by ground personnel, allowing for different geometries based on flight missions, combined with variable rotor blades to optimize performance.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Loss of energy

If variable geometry/pitch stators are incorporated downstream of the rotor to convert swirl to thrust, then efficiency and performance are increased, but complexity and weight increase due to variable geometry mechanisms and actuation systems

Engineering Contradiction:

Improveswirl lossVSAvoidvariable geometry mechanism complexity

Core Design Contradiction:

Loss of energyVSDevice complexity

Solution Approach 1:

The guide vane structure is divided into multiple individual guide vanes that can be independently adjusted to different fixed geometries. Each vane can be manually positioned by ground personnel to optimize performance for specific flight conditions, replacing the need for a single complex variable geometry mechanism that would require actuators and control systems for continuous adjustment during flight.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The guide vane geometries are pre-configured for specific flight conditions (e.g., different pitch angles for climb vs. cruise). Ground personnel manually adjust the vanes to the appropriate pre-determined geometry before flight or between flights, eliminating the need for automated variable geometry systems during flight operations.

Inventive Principle:

Principle #10Preliminary action

2Loss of energy

If variable geometry/pitch stators are incorporated downstream of the rotor to convert swirl to thrust, then efficiency and performance are increased, but weight increases due to mechanisms and actuation systems

Engineering Contradiction:

Improveswirl lossVSAvoidguide vane structure weight

Core Design Contradiction:

Loss of energyVSWeight of moving object

Solution Approach 1:

The guide vane structure is divided into multiple individual guide vanes that can be independently adjusted to different fixed geometries. Each vane can be manually positioned by ground personnel to optimize performance for specific flight conditions, replacing the need for a single complex variable geometry mechanism that would require actuators and control systems for continuous adjustment during flight.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The guide vane geometries are pre-configured for specific flight conditions (e.g., different pitch angles for climb vs. cruise). Ground personnel manually adjust the vanes to the appropriate pre-determined geometry before flight or between flights, eliminating the need for automated variable geometry systems during flight operations.

Inventive Principle:

Principle #10Preliminary action

3Device complexity

If fixed guide vane geometry is used, then system complexity and weight are reduced, but adaptability to different flight conditions is limited

Engineering Contradiction:

Improveguide vane structure complexityVSAvoidadaptability to different flight conditions

Core Design Contradiction:

Device complexityVSAdaptability or versatility

Solution Approach 1:

The guide vane structure is divided into multiple individual guide vanes that can be independently adjusted to different fixed geometries. Each vane can be manually positioned by ground personnel to optimize performance for specific flight conditions, replacing the need for a single complex variable geometry mechanism that would require actuators and control systems for continuous adjustment during flight.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The guide vane structure is designed to perform multiple functions by using different fixed geometries for different flight conditions. The same physical vanes can be configured for climb operations, cruise operations, or other flight phases, providing universal adaptability without requiring separate variable geometry mechanisms for each function.

Inventive Principle:

Principle #6Universality (Multi-functionality)

Data Source

PatentEP4671125A1Open rotor with fixed guide vane/stator

Publication Date: 2025.12.31 RTX CORP

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Figure 3~3A

AI summary

An assembly for an aircraft propulsion system includes an open propulsor rotor (38) having variable geometry propulsor blades (78) and an open guide vane/stator assembly (66) having a plurality of guide vanes (stator blades) (100) in a fixed position relative to the rotor (38) and assembly. The geometry (e.g., pitch, camber, etc.) of the guide vanes (100) can be manually adjusted by ground personnel but are incapable of adjustment during a flight mission (a flight). The open propulsor rotor (38) is configured to rotate about an axis, and the guide vane assembly (66) includes the plurality of guide vanes (100) arranged circumferentially about the axis and is disposed axially next to and downstream of the propulsor rotor (38).