Trapped Vortex Combustor Layout for Stable Downstream Steam Injection
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Turbine engines face challenges in balancing low fuel burn and emissions (NOx, nvPM, CO) while maintaining performance and avoiding flameout, with steam injection in conventional combustors limited by flameout risks and emission reduction capabilities.
Innovation Solution
A combustor design incorporating trapped vortex cavities (TVCs) for fuel combustion and a steam system injecting steam into the main chamber downstream of TVCs, allowing higher steam-to-air ratios without flameout, reducing emissions and specific fuel consumption (SFC).
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Object-generated harmful factors
If steam is injected into the combustion chamber in conventional combustors, then emissions (NOx, nvPM, CO) are reduced, but flameout risk increases and emission reduction capability is limited
Solution Approach 1:
The combustor is divided into separate functional zones: trapped vortex cavities for fuel combustion and a main chamber for steam injection. This segmentation allows steam to be introduced downstream of the flame, reducing emissions without causing flameout in the combustion zone.
Solution Approach 2:
The trapped vortex cavities act as an intermediary structure that separates the fuel combustion process from the steam injection zone. The vortices created in these cavities mix fuel and air effectively while positioning the flame away from direct steam contact, enabling emission reduction without flameout.
2Object-generated harmful factors
If steam-to-air ratio is increased to reduce emissions, then emission reduction capability improves, but flame stability deteriorates
Solution Approach 1:
The design transitions from a single-chamber configuration to a multi-zonal structure with trapped vortex cavities positioned upstream of the main chamber. This spatial arrangement in the longitudinal dimension allows steam injection at high ratios without compromising flame stability in the combustion zone.
Solution Approach 2:
Different regions of the combustor have different functional qualities: the trapped vortex cavities are optimized for fuel combustion with high temperature and low steam content, while the main chamber is designed for steam injection and emission control. This local differentiation enables high steam-to-air ratios while maintaining flame stability where needed.
3Ease of manufacture
If conventional combustor design is used, then structure is simple, but emission reduction capability is limited and flameout risk exists
Solution Approach 1:
The trapped vortex cavities are nested within or adjacent to the main combustor chamber, creating a compact multi-functional structure. This nested arrangement increases emission reduction capability while maintaining relatively simple overall geometry and manufacturing complexity.
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 design achieves reduced emissions and SFC with improved flame stability across various power settings, enabling up to 60% water-to-air ratios and stable operation by injecting steam away from the combustion flame.
Implementation Method 1
A combustor design incorporating trapped vortex cavities (TVCs) for fuel combustion
Implementation Method 2
a steam system injecting steam into the main chamber downstream of TVCs, allowing higher steam-to-air ratios without flameout, reducing emissions and specific fuel consumption (SFC)
Data Source
AI summary
A combustor having a main chamber and a trapped vortex cavity. The main chamber includes an outer liner and an inner liner. The trapped vortex cavity extends from at least one of the outer liner or the inner liner. A plurality of mixing assemblies operably injects a fuel-air mixture into the trapped vortex cavity to produce combustion gases. The trapped vortex cavity injects the combustion gases into the main chamber. A steam system is in fluid communication with the main chamber. The steam system operably injecting steam into the main chamber such that the steam flows downstream of the trapped vortex cavity.