Variable Airfoil Sealed Flowpath for Gas Turbine Leakage Reduction

Solution Overview

Problem

Gas turbine engines with variable stator vanes experience airflow leakage around their radially inner and outer ends due to lack of fixed attachment, affecting performance, efficiency, and durability.

Innovation Solution

The design incorporates a variable vane assembly with a fixed and a moveable member forming seal interfaces along the radial direction, where the moveable member is pivotally coupled to an airfoil band, minimizing leakage by forming airtight seals with the band and maintaining airflow direction variability.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Productivity

If variable stator vanes are made moveable to vary airflow direction, then engine performance and efficiency are improved, but airflow leakage occurs around the radial ends of the vanes

Engineering Contradiction:

Improveengine performanceVSAvoidairflow leakage

Core Design Contradiction:

ProductivityVSLoss of energy

Solution Approach 1:

The airfoil is divided into two separate members: a first member that is fixedly attached to the airfoil band, and a second member that is moveably attached. This segmentation allows the first member to provide stable sealing at the radial ends while the second member provides variable airflow direction control, thus resolving the contradiction between performance improvement and airflow leakage prevention.

Inventive Principle:

Principle #1Segmentation

2Productivity

If variable stator vanes are made moveable to vary airflow direction, then engine efficiency is improved, but sealing at radial ends deteriorates

Engineering Contradiction:

Improveengine efficiencyVSAvoidsealing capability

Core Design Contradiction:

ProductivityVSReliability

Solution Approach 1:

The airfoil is divided into two separate members: a first member that is fixedly attached to the airfoil band, and a second member that is moveably attached. This segmentation allows the first member to provide stable sealing at the radial ends while the second member provides variable airflow direction control, thus resolving the contradiction between performance improvement and airflow leakage prevention.

Inventive Principle:

Principle #1Segmentation

3Adaptability or versatility

If variable stator vanes are made moveable to vary airflow direction, then airflow direction variability is improved, but structural stability deteriorates

Engineering Contradiction:

Improveairflow direction variabilityVSAvoidstructural stability

Core Design Contradiction:

Adaptability or versatilityVSStability of the object's composition

Solution Approach 1:

The airfoil is divided into two separate members: a first member that is fixedly attached to the airfoil band, and a second member that is moveably attached. This segmentation allows the first member to provide stable sealing at the radial ends while the second member provides variable airflow direction control, thus resolving the contradiction between performance improvement and airflow leakage prevention.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The second member of the airfoil is configured to be moveably attached to the airfoil band, allowing it to change position to vary the airflow direction. This dynamic configuration enables the vane to adapt to different operating conditions while the first member maintains structural stability, resolving the contradiction between adaptability and stability.

Inventive Principle:

Principle #15Dynamics

Data Source

PatentUS10815821B2Variable airfoil with sealed flowpath

Publication Date: 2020.10.27 GENERAL ELECTRIC CO

AI summary

A stage of guide vanes for a machine includes a first variable vane assembly including an airfoil. The airfoil of the first variable vane assembly includes a first member and a second member each extending generally along a radial direction and the second member being moveable relative to the first member. The stage of guide vanes also includes a second variable vane assembly including an airfoil, the airfoil of the second variable vane assembly including a first member and a second member each extending generally along the radial direction and the second member being moveable relative to the first member, the second members of the airfoils of the first and second variable vane assemblies being moveable towards one another.