Gas Turbine Airfoil Panel Retained by Preloaded Compliant Member

Solution Overview

Problem

Gas turbine engines face inefficiencies due to the need for compressor bleed cooling, which penalizes engine efficiency by relying on pressure differential, making it challenging to reduce compressor bleed volume, increase velocity, or raise temperature while maintaining high pressure and low temperature requirements.

Innovation Solution

The introduction of an airfoil structure with an interior cavity, a preloaded compliant member, and a panel that defines a portion of the airfoil profile, where the preloaded compliant member, such as a mechanical spring or baffle, retains the panel in a seated position, enhancing thermal resistance and reducing the need for compressor bleed cooling.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Temperature

If compressor bleed cooling is used to cool the turbine inlet, then the turbine inlet temperature is reduced, but the engine efficiency deteriorates due to the need for large compressor bleed volume and pressure differential

Engineering Contradiction:

Core Design Contradiction:

TemperatureVSLoss of energy

Solution Approach 1:

The airfoil is divided into multiple panels that can be independently positioned and adjusted. This segmentation allows for localized thermal management at different regions of the airfoil, enabling targeted cooling where needed while maintaining engine efficiency by reducing overall compressor bleed volume requirements

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The patent employs adjustable panels with actuators that can dynamically change the airfoil geometry in response to varying thermal conditions. This dynamic adjustment allows the system to optimize cooling effectiveness while minimizing the energy penalty associated with compressor bleed cooling

Inventive Principle:

Principle #15Dynamics

2Loss of energy

If compressor bleed volume is reduced, then engine efficiency is improved, but the ability to maintain adequate cooling at the turbine inlet deteriorates

Engineering Contradiction:

Core Design Contradiction:

Loss of energyVSTemperature

Solution Approach 1:

The airfoil incorporates panels with different thermal properties and geometries tailored to specific locations. High-heat-flux regions receive enhanced cooling through specially designed panels, while lower-heat-flux regions use standard panels, allowing effective thermal management with reduced overall compressor bleed volume

Inventive Principle:

Principle #3Local quality

Solution Approach 2:

The system changes geometric parameters of the airfoil panels to optimize thermal performance. By adjusting panel positions, angles, and configurations, the system enhances local cooling effectiveness while maintaining reduced compressor bleed volume requirements

Inventive Principle:

Principle #35Parameter changes

3Manufacturing precision

If the panel is rigidly fixed to the airfoil structure, then manufacturing precision is improved, but the ability to accommodate thermal expansion differences deteriorates

Engineering Contradiction:

Core Design Contradiction:

Manufacturing precisionVSAdaptability or versatility

Solution Approach 1:

The patent employs flexible panel connections and compliant mechanisms that allow panels to move and adjust their positions. This flexibility accommodates thermal expansion and contraction of different airfoil components while maintaining precise panel positioning through controlled actuation and mechanical constraints

Inventive Principle:

Principle #30Flexible shells and thin films

Solution Approach 2:

The panel assembly includes self-adjusting mechanisms that automatically compensate for thermal expansion differences between panels and the airfoil structure. The system uses spring-loaded actuators and compliant joints that maintain optimal panel positioning without external control, accommodating thermal variations while preserving manufacturing precision

Inventive Principle:

Principle #25Self-service

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 thermal resistance at the compressor exit and turbine inlet, improving engine efficiency by reducing the need for compressor bleed cooling and maintaining a positive force on the panel despite thermal expansion differences, thus optimizing engine performance.

Implementation Method 1

a preloaded compliant member in the interior cavity, where the preloaded compliant member compliantly retains the panel in a seated position on the airfoil structure

Methodology Applied

Scientific EffectElasticity: Elasticity

Implementation Method 2

maintaining a positive force on the panel despite thermal expansion differences

Methodology Applied

Scientific EffectThermal expansion: Thermal Expansion

Data Source

PatentUS10408090B2Gas turbine engine article with panel retained by preloaded compliant member

Publication Date: 2019.09.10

AI summary

An airfoil includes an airfoil structure that has an interior cavity, a preloaded compliant member in the interior cavity, and a panel that defines a portion of an airfoil profile. The preloaded compliant member compliantly retains the panel in a seated position on the airfoil structure.