Combustor Floating Collar Louver Film Cooling
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Cooling of the downstream or combustion side of heat shields in gas turbine combustors is challenging and requires improvement to ensure constant and effective cooling.
Innovation Solution
A floating collar and heat shield assembly that allows relative movement between the combustor and fuel nozzle, featuring a radially disposed annular louver and a sealing ring to direct cooling air to a controlled gap between the louver and heat shield, providing film cooling to the hot surface of the heat shield.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Object-affected harmful factors
If a heat shield is used to protect the combustor, then protection is improved, but cooling difficulty increases
Solution Approach 1:
The cooling system is segmented into multiple functional zones: a first cooling region for the upstream surface and a second cooling region for the downstream surface. Each region has dedicated cooling air passages and flow paths, allowing independent optimization of cooling for each surface while maintaining the heat shield's protective function.
Solution Approach 2:
Cooling air acts as an intermediary substance that is directed through specific passages and gaps to reach the heat shield surfaces. The cooling air flows through a first gap to the upstream surface and through a second gap to the downstream surface, serving as the medium that transfers cooling effect to the protected components.
2Temperature
If cooling air is directed to the downstream surface, then cooling effectiveness is improved, but sealing requirements increase
Solution Approach 1:
The system accommodates dynamic radial movement of the fuel nozzle and collar relative to the heat shield through flexible sealing arrangements. The sealing ring and O-ring seal engage with the collar and heat shield respectively, maintaining sealing effectiveness while allowing the components to move radially during operation without compromising the cooling air flow paths.
Solution Approach 2:
The sealing ring and O-ring seal act as intermediary sealing elements that maintain the integrity of the cooling air flow paths while accommodating relative movement between components. These sealing intermediaries ensure that cooling air is effectively directed to the downstream surface without leakage, balancing cooling effectiveness with sealing requirements.
3Adaptability or versatility
If relative movement is allowed between combustor and fuel nozzle, then adaptability is improved, but sealing complexity increases
Solution Approach 1:
The floating collar is designed to allow radial movement relative to both the combustor and the heat shield, providing adaptability to thermal expansion and operational variations. The sealing ring and O-ring seal are positioned to engage with the collar and heat shield respectively, maintaining sealing effectiveness while allowing this dynamic movement without requiring complex rigid sealing mechanisms.
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 assembly effectively enhances heat shield cooling by creating a controlled gap for coolant flow, improving heat shield protection and reducing leakage while accommodating radial excursion of the fuel nozzle and collar, thus maintaining efficient cooling.
Implementation Method 1
the louver directing a film of coolant along a hot front surface of the heat shield
Implementation Method 2
said louver and said heat shield defining a controlled gap therebetween... feeding cooling air to said controlled gap
Data Source
AI summary
A gas turbine combustor is provided with a dome heat shield having a fuel nozzle opening, the opening receiving a floating collar assembly for permitting relative movement between nozzle and heat shield. The floating collar is provided with a louver to provide film cooling to the face of the combustor heat shield and, thus, improve cooling thereof.