Gas Turbine Combustor Dome Cooling for Heat Shield Durability
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The heat shields in gas turbine engine combustors experience premature wear and failure due to exposure to high temperatures, which is not effectively addressed by existing technologies.
Innovation Solution
A combustor assembly with a combustor dome featuring cooling holes that direct cooling airflow onto a heat deflector lip of a heat shield, maintaining the heat shield within a desired operating temperature range and protecting attached fuel-air injector hardware components.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the heat shield is exposed to high temperatures in the combustion chamber, then it can protect the fuel-air injector hardware assembly, but the heat shield experiences premature wear and failure
Solution Approach 1:
A cooling airflow is introduced as an intermediary substance between the heat shield and the high-temperature combustion environment. The cooling air flows through or over the heat shield, creating a thermal barrier that reduces heat transfer to the heat shield while maintaining its protective function for the fuel-air injector hardware assembly
Solution Approach 2:
The thermal parameters of the heat shield environment are changed by introducing cooling airflow. This modifies the temperature distribution and heat flux conditions, transforming the extreme thermal environment into a more manageable one that extends heat shield life while preserving its protective capability
2Temperature
If cooling airflow is directed onto the heat deflector lip, then the heat shield temperature is reduced, but the device complexity increases
Solution Approach 1:
The cooling airflow path is extracted and directed through existing openings in the combustor dome structure. By utilizing pre-existing geometric features rather than adding dedicated cooling channels, the solution reduces the added complexity while still achieving effective cooling of the heat deflector lip
Solution Approach 2:
The cooling airflow system serves multiple functions simultaneously: it cools the heat shield, protects the fuel-air injector hardware, and can be integrated with existing combustor air supply systems. This multi-functionality reduces overall system complexity by consolidating cooling requirements into a single airflow path
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 solution effectively reduces heat shield wear and failure, allowing for prolonged operation and maintaining the fuel-air injector hardware components within a safe temperature range, while maintaining a compact and lightweight combustor design.
Implementation Method 1
The cooling hole in the combustor dome is oriented to direct a cooling airflow onto the heat deflector lip
Implementation Method 2
The heat shield defines a circumferential channel, and the cooling hole in the combustor dome is oriented to direct a cooling airflow into the circumferential channel
Data Source
Figure 1
Figure 2
Figure 3
AI summary
A combustor assembly (100) for a gas turbine engine includes a combustor dome (102) defining an opening (144), a cooling hole (154), and at least in part defining a combustion chamber (108). The combustor dome (102) includes a first side (150) and a second side (152), the cooling hole (154) extending from the first side (150) to the second side (152). The combustor assembly (100) additionally includes a fuel-air injector hardware assembly (146) positioned at least partially within the opening (144) of the combustor dome (102) and including a heat shield (158). The heat shield (158) includes a heat deflector lip (162). The cooling hole (154) in the combustor dome (102) is oriented to direct a cooling airflow onto the heat deflector lip (162) to maintain at least a portion of the heat shield (158) within a desired operating temperature range.