Combustion Device Intermediate Air Supply for Turbine Efficiency
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The existing sequential combustion gas turbines face performance and efficiency issues due to the high pressure air being drawn from the compressor's last stage, which negatively impacts combustion and expansion processes, leading to reduced efficiency and increased NOx emissions.
Innovation Solution
The combustion device incorporates a burner with vortex generators and a lance for fuel and air injection, where air is supplied from an intermediate compressor stage, minimizing pressure losses and maintaining air pressure close to the exhaust gases, thereby reducing the negative impact on turbine performance and NOx emissions.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Stress or pressure
If air is drawn from the last stage of the compressor to supply the second combustion device, then the air pressure is sufficient to penetrate into the high pressure exhaust gases, but the gas turbine performance and efficiency are negatively impacted due to large pressure losses
Solution Approach 1:
The patent changes the parameter of air supply pressure by drawing air from an intermediate stage of the compressor rather than the last stage. This intermediate pressure is sufficient for fuel penetration into exhaust gases but causes minimal pressure losses, thereby resolving the contradiction between maintaining adequate air pressure and preserving gas turbine efficiency.
2Quantity of substance
If air is drawn from the last stage of the compressor, then fuel penetration into exhaust gases is improved, but NOx emissions increase due to disrupted combustion and expansion processes
Solution Approach 1:
The patent modifies the air supply pressure parameter by sourcing air from an intermediate compressor stage. This maintains adequate pressure for fuel penetration into exhaust gases while avoiding the excessive pressure disruption that leads to incomplete combustion and increased NOx emissions, thus resolving the contradiction between fuel penetration and emission control.
3Stress or pressure
If air is drawn from the last stage of the compressor, then the air pressure matches the exhaust gases pressure, but the combustion and expansion processes are negatively impacted
Solution Approach 1:
The patent optimizes the air pressure parameter by selecting an intermediate compressor stage that provides sufficient pressure for fuel injection without creating the excessive pressure imbalance that disrupts combustion stability and expansion processes, thereby resolving the contradiction between pressure matching and process reliability.
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 design enhances fuel penetration, reduces NOx emissions, and improves overall combustion device efficiency by maintaining air pressure similar to the exhaust gases, thereby increasing the flashback margin and reducing the negative impact on gas turbine performance.
Implementation Method 1
a burner (10) with vortex generators (13)
Implementation Method 2
a lance (14) for fuel and air injection
Implementation Method 3
additional fuel is supplied into the exhaust gases and it is combusted to generate hot gases
Data Source
Figure 1~3
Figure 4~5
Figure 6
AI summary
The combustion device includes a burner, a combustion chamber downstream of the burner, a lance projecting into the burner for fuel and air injection, and a plenum that at least partly houses the burner. The plenum is connected to the inside of the lance to supply an oxidiser to it.