Magnetic Seal Assembly for Turbomachine Thermal Misalignment
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional sealing assemblies in gas turbine engines face durability issues due to high temperatures and thermal expansion, leading to misalignment and incomplete sealing, which reduces their lifespan and effectiveness.
Innovation Solution
A magnetic sealing arrangement is implemented, using magnets coupled to the aft frame and stage one nozzle, with a shell surrounding the magnets to maintain alignment and prevent leakage, while a heat shield and cooling system help manage temperature and prevent damage.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If conventional sealing assemblies are used in high temperature environments, then sealing function is provided, but durability decreases due to thermal expansion and misalignment
Solution Approach 1:
The patent replaces conventional mechanical sealing systems with a magnetic sealing system. Magnets are positioned on opposite sides of the gap between the transition duct and turbine inlet, creating magnetic attraction forces that maintain sealing contact without mechanical constraints. This substitution eliminates the thermal expansion and misalignment issues that plague mechanical seals in high-temperature environments, as magnetic fields are not affected by thermal conditions.
Solution Approach 2:
The patent changes the sealing mechanism from mechanical contact to magnetic field interaction. By utilizing magnetic field strength as the sealing parameter instead of mechanical contact pressure, the system can maintain effective sealing across varying temperatures. The magnetic attraction force remains consistent regardless of thermal expansion, allowing the sealing gap to be maintained without mechanical misalignment.
2Manufacturing precision
If conventional sealing assemblies are used, then initial sealing is achieved, but alignment is lost during operation due to thermal expansion and vibration
Solution Approach 1:
The magnetic sealing system replaces mechanical alignment mechanisms with magnetic field-based positioning. The magnets create attractive forces that actively maintain alignment between the transition duct and turbine inlet components during operation. This eliminates the problem of thermal expansion and vibration causing misalignment, as the magnetic field dynamically compensates for positional changes without requiring precise mechanical tolerances.
3Reliability
If magnets are used for sealing, then durability and alignment are improved, but device complexity increases due to additional components
Solution Approach 1:
The magnets in the sealing assembly serve multiple functions simultaneously: they provide the sealing force by creating magnetic attraction across the gap, they maintain alignment between components, and they compensate for thermal expansion and vibration. This multi-functionality reduces the need for separate mechanical sealing, alignment, and compensation mechanisms, thereby limiting the increase in overall device complexity despite the introduction of magnetic components.
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 magnetic sealing arrangement enhances durability and alignment, ensuring a consistent seal across the gap, prolonging the assembly's life and maintaining efficient energy transfer by preventing combustion gas dilution with pressurized air.
Implementation Method 1
A first magnet is coupled to the aft frame and a second magnet is coupled to the stage one nozzle
Implementation Method 2
A shell is coupled to and at least partially surrounds between the first magnet and the second magnet
Data Source
AI summary
Sealing arrangements and turbomachines are provided. A sealing arrangement includes a transition duct having an upstream end and a downstream end. The transition duct includes an aft frame that circumferentially surrounds the downstream end of the transition duct. A stage one nozzle is spaced apart from the aft frame and defines a gap therebetween. A sealing assembly extends across the gap and is magnetically coupled to both the aft frame and the stage one nozzle. The sealing assembly includes a first magnet coupled to the aft frame and a second magnet coupled to the stage one nozzle. The sealing assembly further includes a shell that is coupled to and at least partially surrounds the first magnet and the second magnet.