Segmented Seal Ring for Gas Turbine Compressor Thermal Management

Solution Overview

Problem

High-pressure compressor sections in gas turbine engines face challenges with thermal loads and operational life due to higher operating temperatures and pressure ratios, which affect the sealing efficiency and longevity of components.

Innovation Solution

A rotating seal ring system is introduced, comprising an axial arm positioned between the integrally bladed rotor and the hub rotor, decoupled from the outer shaft, allowing for easy replacement and featuring abradable blades to form a seal between high-temperature gas paths, reducing thermal stress and facilitating maintenance.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If a rotating seal is used in high-pressure compressor sections with higher operating temperatures and pressure ratios, then sealing efficiency is improved, but thermal loads increase causing low-cycle fatigue and creep

Engineering Contradiction:

Improvesealing efficiencyVSAvoidthermal resistance

Core Design Contradiction:

ReliabilityVSStrength

Solution Approach 1:

The seal ring is divided into multiple axial arms (first axial arm, second axial arm, etc.) that are separably coupled to the integrally bladed rotor. Each axial arm can be independently removed and replaced, allowing the seal ring to be segmented into discrete replaceable units rather than a single monolithic component.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The seal ring is designed with modified geometric parameters including the axial arms extending axially from the integrally bladed rotor, with specific arm spacing and dimensional relationships that optimize sealing performance while distributing thermal stresses across multiple contact points rather than concentrating them.

Inventive Principle:

Principle #35Parameter changes

2Strength

If the seal ring is integrally coupled to the integrally bladed rotor, then structural strength is improved, but maintenance difficulty increases due to inability to easily replace worn components

Engineering Contradiction:

Improvestructural integrityVSAvoidmaintenance accessibility

Core Design Contradiction:

StrengthVSEase of repair

Solution Approach 1:

The seal ring is divided into multiple axial arms (first axial arm, second axial arm, etc.) that are separably coupled to the integrally bladed rotor. Each axial arm can be independently removed and replaced, allowing the seal ring to be segmented into discrete replaceable units rather than a single monolithic component.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The coupling between the axial arms and the integrally bladed rotor is designed to be dynamically adjustable, allowing the axial arms to be attached or detached as needed. This enables the seal ring to transition from a fixed integral structure to a modular assembly that can be maintained without replacing the entire rotor assembly.

Inventive Principle:

Principle #15Dynamics

3Power

If higher pressure ratios are used in the high-pressure compressor section, then power output is improved, but thermal stress on seal components increases reducing operational life

Engineering Contradiction:

Improvepower outputVSAvoidoperational life

Core Design Contradiction:

PowerVSDuration of action of stationary object

Solution Approach 1:

The seal ring is divided into multiple axial arms (first axial arm, second axial arm, etc.) that are separably coupled to the integrally bladed rotor. Each axial arm can be independently removed and replaced, allowing the seal ring to be segmented into discrete replaceable units rather than a single monolithic component.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The seal ring with its axial arms is pre-configured and pre-assembled on the integrally bladed rotor before operation. This preliminary assembly ensures proper positioning and alignment of the sealing surfaces, allowing the high-pressure compressor to operate at optimal pressure ratios from the start without requiring adjustments during operation.

Inventive Principle:

Principle #10Preliminary action

Data Source

PatentEP3081748B1Gas turbine engine system comprising a seal ring

Publication Date: 2020.12.16 RTX CORP

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AI summary

A seal ring (202) for use between an integrally bladed rotor (200) and a hub rotor (204) of a compressor section (24) of a gas turbine engine (20) includes an arm (310) configured to be positioned between the integrally bladed rotor (200) and the hub rotor (204), such that the seal ring (202) is removably coupled to the integrally bladed rotor (200) and the hub rotor (204) in response to a compressive force applied to the arm (310) by the integrally bladed rotor (200) and the hub rotor (204). The seal ring (202) also includes a first blade (314A) coupled to the arm (310) and configured to form a seal between a first volume and a second volume. A system of a gas turbine engine comprising such a seal ring is also provided.