Redundant Endrail Combustor Panel Cooling Cavity Design

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Combustor panels in gas turbine engines are susceptible to structural damage and oxidation due to high temperatures, leading to reduced operational life and potential 'burnthrough' when exposed to hot combustion gases.

Innovation Solution

The design incorporates redundant endrails on combustor panels with equal heights, forming an annular cooling cavity and utilizing impingement holes to deliver cooling air, which maintains effusion cooling even if one endrail is damaged, preventing rapid oxidation and extending panel life.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If a single endrail is used on combustor panels, then the structure is simpler and easier to manufacture, but the panel is more susceptible to rapid oxidation and burnthrough when the endrail is damaged

Engineering Contradiction:
Improveoxidation resistanceVSAvoidendrail configuration
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The patent applies beforehand cushioning by providing a redundant endrail that serves as a pre-prepared backup. When the primary endrail is damaged or oxidized, the redundant endrail immediately takes over to maintain the cooling air flow and protect the panel edge, preventing rapid oxidation and burnthrough. This redundancy is built into the design in advance to cushion against potential failures.

Inventive Principle:
Principle #11Beforehand cushioning (Prior cushioning)

Solution Approach 2:

The patent applies local quality by providing different functions to different parts of the endrail structure. The primary endrail handles normal cooling operations, while the redundant endrail remains standby until needed. This creates localized functional zones within the endrail assembly, optimizing both reliability and resource utilization.

Inventive Principle:
Principle #3Local quality

2Duration of action of stationary object

If redundant endrails are added to combustor panels, then oxidation resistance and operational life are improved, but the manufacturing complexity and material usage increase

Engineering Contradiction:
Improvepanel operational lifeVSAvoidendrail fabrication
Core Design Contradiction:
Duration of action of stationary objectVSEase of manufacture

Solution Approach 1:

The patent applies merging by integrating the redundant endrail with the primary endrail into a unified structure. Both endrails are positioned adjacent to each other and work together as a single cooling system, sharing the same cooling air flow path and structural support. This reduces manufacturing steps compared to installing separate independent endrails.

Inventive Principle:
Principle #5Merging (Combining)

Solution Approach 2:

The redundant endrail serves multiple functions: it acts as a backup cooling structure, maintains the cooling air flow path, provides structural support, and prevents panel edge exposure to hot gases. This multi-functionality justifies the additional material usage by delivering multiple benefits from a single structural addition.

Inventive Principle:
Principle #6Universality (Multi-functionality)

3Ease of operation

If the distance between endrails is increased, then manufacturing tolerance is more lenient and assembly is easier, but the cooling air flow efficiency and pressure gradient are reduced

Engineering Contradiction:
Improveassembly toleranceVSAvoidcooling efficiency
Core Design Contradiction:
Ease of operationVSProductivity

Solution Approach 1:

The patent applies parameter changes by optimizing the distance between endrails to a specific range (0.05-1.0 inch) that balances manufacturing ease with cooling efficiency. This parameter optimization ensures that the cooling air flow is not excessively restricted while maintaining reasonable assembly tolerances. The impingement hole dimensions are also adjusted to compensate for variations in endrail spacing.

Inventive Principle:
Principle #35Parameter changes

4Temperature

If impingement holes are added to deliver cooling air to the endrail gap, then cooling efficiency is improved, but the panel structure becomes more complex

Engineering Contradiction:
Improvecooling air deliveryVSAvoidcooling cavity structure
Core Design Contradiction:
TemperatureVSDevice complexity

Solution Approach 1:

The patent applies self-service by allowing the cooling air system to serve itself. The impingement holes automatically deliver cooling air to the endrail gap without requiring external control mechanisms. The cooling air flow is driven by the pressure gradient that naturally develops in the cooling cavity, eliminating the need for additional actuators or control systems.

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

The redundant endrail configuration ensures sustained cooling air flow and pressure gradient, preventing rapid oxidation and extending the operational life of combustor panels by maintaining effective effusion cooling despite potential damage.

Implementation Method 1

The redundant endrail configuration ensures sustained cooling air flow and pressure gradient

Methodology Applied
Scientific EffectPressure gradient: Pressure Gradient

Data Source

PatentEP3404330B1Redundant endrail for combustor panel
Publication Date: 2020.07.01 RTX CORP
  • EP3404330B1 patent drawingFigure 1
  • EP3404330B1 patent drawingFigure 2
  • EP3404330B1 patent drawingFigure 3

AI summary

A combustor panel (111) may include a body (120) having an edge, a first endrail (121) disposed along the edge of the body (120), and a second endrail (122) disposed adjacent the first endrail (121), wherein a volume (118) is defined between the first endrail (121) and the second endrail (122). The first endrail (121) may have a first height, measured from the body (120) to a first tip (126) of the first endrail (121), and the second endrail (122) may have a second height, measured from the body (120) to a second tip (127) of the second endrail (122), wherein the first height is the same as the second height. The second endrail (122) may include an endrail hole (135) extending through the second endrail (122).