Sealed Combustor Liner Panel With Impingement Film Floatwall Cooling
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Gas turbine engine combustors face challenges in maintaining effective cooling at high compressor exit temperatures and reduced supply pressures, particularly at high altitudes, where conventional cooling methods are insufficient due to decreased heat transfer capability.
Innovation Solution
The implementation of an Impingement Film Floatwall (IFF) assembly within the combustor, featuring impingement passages, effusion passages, and a C-shaped seal, which enhances cooling by creating a pressure drop across the combustor walls, allowing for efficient heat removal through internal convection and film cooling, thereby protecting the liner panels from high-temperature combustion gases.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If conventional cooling methods are used in combustor, then the structure is simple, but cooling effectiveness deteriorates at high compressor exit temperatures and reduced supply pressures
Solution Approach 1:
The cooling system is segmented into multiple functional components: impingement passages for direct cooling, effusion passages for film cooling, and a C-shaped seal for sealing. This segmentation allows each component to perform its specific cooling function efficiently, resolving the contradiction between cooling effectiveness and structural simplicity.
Solution Approach 2:
The cooling passages are nested within the liner panel structure, with impingement passages and effusion passages integrated into the panel walls. The C-shaped seal is nested within a groove on the panel surface. This nesting approach embeds complex cooling functionality within the existing structural framework, maintaining relative simplicity while achieving high cooling effectiveness.
2Power
If high compressor exit temperatures are operated, then power output is improved, but heat load on combustor walls increases
Solution Approach 1:
Cooling air acts as an intermediary substance between the high-temperature combustion gases and the combustor walls. The cooling air is introduced through impingement passages to directly cool the inner wall surface, and through effusion passages to form a protective film, thereby mediating the heat transfer and protecting the walls from excessive heat loads while allowing high power operation.
Solution Approach 2:
The cooling system utilizes pneumatic principles by introducing pressurized cooling air through impingement and effusion passages. The pressurized air flow creates effective cooling through convection and film formation, enabling the combustor to withstand high heat loads associated with high power output operations.
3Adaptability or versatility
If supply pressure is reduced at high altitude, then flight envelope is expanded, but convection and radiation heat loads increase
Solution Approach 1:
Cooling air is supplied in advance through the impingement and effusion passages before the combustor walls are exposed to high heat loads. This preliminary cooling action establishes protective cooling layers and film structures that prevent excessive heat accumulation, enabling the combustor to operate reliably under reduced supply pressure conditions at high altitude.
Solution Approach 2:
The cooling system applies different cooling mechanisms to different locations: impingement cooling for areas requiring direct wall cooling and effusion cooling for areas requiring film protection. This localized quality approach optimizes heat load management across the combustor surface, enabling expanded flight envelope operation despite increased convection and radiation heat loads.
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 solution significantly increases the cooling effectiveness of the combustor walls, minimizing leakage and maintaining efficient heat removal even at reduced altitudes, ensuring the combustor operates reliably under demanding conditions.
Implementation Method 1
The seal minimizes leakage from the cooling passage to the combustion chamber, thereby facilitating the formation of a greater pressure drop across the liner panel and/or support shell
Implementation Method 2
allowing for efficient heat removal through internal convection and film cooling
Implementation Method 3
allowing for efficient heat removal through internal convection and film cooling
Data Source
Figure 1
Figure 2
Figure 3
AI summary
A liner panel for a combustor of a gas turbine engine includes a rail which at least partially defines an impingement cavity. The rail includes a notch which faces toward the impingement cavity. A method of cooling a wall assembly within a combustor of a gas turbine engine includes directing air through a support shell and a liner panel to form a pressure drop across the support shell that is less than about 80% of a pressure drop across the combustor and to also form a pressure drop across the liner panel greater than about 20% of the pressure drop across the combustor.