Gas Turbine Combustor Panel Cooling Flow Design
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Gas turbine engine combustor panels face challenges in effectively cooling high-temperature areas without generating NOx pollutants, as traditional film cooling methods often intermix cooling air with swirling air and fuel, leading to nitrogen scavenging and increased NOx formation.
Innovation Solution
The design features heat-resistant panels with strategically positioned exit ports directing cooling air in opposed axial directions, eliminating film cooling holes between ports, and using air supply ports to impinge cooling air on outer panel faces, aligning with fluid circulation from the swirler to reduce collisions and NOx formation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Temperature
If traditional film cooling holes are used to cool the panel, then cooling effectiveness is improved, but cooling air intermixes with swirling air and fuel causing nitrogen scavenging and increased NOx formation
Solution Approach 1:
The panel cooling system is segmented into multiple zones with different cooling mechanisms: film cooling holes in the downstream portion and opposed axial exit ports at upstream and downstream ends. This segmentation allows different cooling strategies to be applied in different locations to optimize both cooling effectiveness and NOx reduction.
Solution Approach 2:
Instead of using traditional film cooling holes that allow cooling air to mix with the combustion flow, the invention uses exit ports that direct cooling air in opposed axial directions parallel to the swirl flow. This inverted approach prevents nitrogen scavenging and NOx formation while still achieving effective cooling.
2Temperature
If cooling air is directed opposite to swirl flow direction, then cooling air effectiveness is improved, but this creates harmful intermixing and nitrogen scavenging
Solution Approach 1:
Different regions of the panel are provided with different cooling characteristics: the upstream portion uses exit ports directing cooling air upstream, the downstream portion uses exit ports directing cooling air downstream, and film cooling holes are eliminated in the upstream portion. This local differentiation optimizes cooling effectiveness while preventing harmful intermixing in critical regions.
3Object-generated harmful factors
If exit ports direct cooling air in opposed axial directions, then NOx formation is reduced, but device complexity increases compared to traditional film cooling
Solution Approach 1:
The exit ports serve multiple functions: they provide cooling air to the panel, direct cooling air in opposed axial directions to reduce NOx formation, and eliminate the need for separate film cooling holes in certain regions. This multi-functionality reduces overall system complexity despite the sophisticated flow control required.
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 approach reduces NOx emissions by minimizing collisions between oxygen and nitrogen, effectively cooling the combustor components while maintaining a lower temperature air stream, thus reducing nitrogen scavenging and NOx contaminants.
Implementation Method 1
the exit ports are configured to direct cooling air in the first and second directions consistent with a circulation of fluids exiting the swirler
Implementation Method 2
maintaining a lower temperature air stream, thus reducing nitrogen scavenging and NOx contaminants
Data Source
AI summary
A heat resistant panel has a bulkhead and a swirler adjacent a combustion chamber. The heat resistant panel comprises an inner panel for facing the combustion chamber and defining a first exit port at an upstream end thereof configured to direct cooling air into the combustor chamber in a first direction adjacent the bulkhead. A second exit port at a downstream end thereof is configured to direct cooling air into the combustor chamber in a second direction with an axial direction defined between the upstream and downstream ends. The first and second directions have opposed axial components. A heat resistant structure and a combustor are also disclosed.