Integrated Clearance Control Ring for Gas Turbine Blade Tip Adjustment
Solution Overview
Problem
Current bolted flange arrangements in gas turbine engines are difficult to machine and assemble, limiting the ability to adjust blade tip clearances effectively, which affects engine efficiency.
Innovation Solution
A clearance control assembly featuring a 'T' shaped clearance control ring with a cap and stem portion, positioned axially between a radially extending flange and an inner diffuser case, using materials with different thermal expansion coefficients to control blade tip clearances, and including a heat shield and mechanical fasteners to secure the blade outer air seal assembly.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If bolted flange arrangements are used for clearance control rings, then the structural strength and reliability are improved, but the manufacturing complexity and assembly difficulty increase significantly
Solution Approach 1:
The patent merges the clearance control ring with the blade outer air seal assembly into a single integrated component. The clearance control ring is formed as an integral part of the air seal assembly, eliminating the need for separate bolted flange connections. This integration maintains structural reliability while dramatically simplifying manufacturing and assembly operations.
Solution Approach 2:
The integrated assembly combines multiple functions into a single component structure. The blade outer air seal assembly simultaneously provides sealing functionality and clearance control capabilities through its integrated ring structure, eliminating the need for separate fastening components and reducing overall assembly complexity.
2Stability of the object's composition
If bolted flange arrangements are used for clearance control rings, then the structural stability is improved, but the manufacturing precision and adjustment capability deteriorate
Solution Approach 1:
The integration of the clearance control ring with the air seal assembly enables precise manufacturing of a single monolithic component. This eliminates cumulative tolerances associated with multiple bolted joints, allowing for more precise control of blade tip clearances while maintaining structural stability through the unified geometry.
3Adaptability or versatility
If multiple separate components are used for clearance control, then the adaptability and adjustability are improved, but the assembly time and production efficiency worsen
Solution Approach 1:
The patent achieves both adaptability and productivity by integrating the clearance control ring into the air seal assembly. The design incorporates adjustable features within the integrated structure, such as modifiable geometries or selective material properties, that allow clearance adjustment capabilities while maintaining a single-component architecture for rapid installation and manufacturing.
4Temperature
If different materials with different thermal expansion coefficients are used, then the thermal expansion management is improved, but the manufacturing complexity and material selection difficulty increase
Solution Approach 1:
The integrated clearance control ring and air seal assembly can be manufactured as a composite structure or from graded materials with varying thermal expansion properties. This allows different regions of the single component to exhibit different thermal behaviors, managing thermal expansion effectively while maintaining manufacturing simplicity through monolithic construction.
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
Enables precise adjustment and control of blade tip clearances, reducing assembly time, stress concentrations, and improving durability by allowing thermal expansion management without mechanical fasteners, thus enhancing engine efficiency and compactness.
Implementation Method 1
the clearance control ring comprises a second material having a second coefficient of thermal expansion that is different than the first coefficient of thermal expansion
Data Source
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AI summary
A clearance control assembly for a gas turbine engine according to an exemplary aspect of the present disclosure includes, among other things, a clearance control ring to position a blade outer air seal assembly radially relative to a blade tip. The clearance control ring is compression fit to the blade outer air seal assembly.