Gas Turbine Airfoil Leading Edge Cooling with Segmented Circuits
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Cooling the leading edges of gas turbine engine components downstream of variable vanes is challenging due to high heat transfer coefficients and significant changes in stagnation point location, which affect the efficiency and effectiveness of existing cooling methods.
Innovation Solution
A multicavity cooling design with separate cooling circuits and film holes arranged in radial rows to maintain effective cooling across varying incidence angles, ensuring robust cooling and minimizing hot gas ingestion, with each circuit designed to handle large swings in external static pressures.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If variable vanes are actuated to alter flow, then engine performance is improved, but cooling effectiveness at the leading edge deteriorates due to changing stagnation point location and increased heat transfer coefficients
Solution Approach 1:
The cooling system is divided into multiple independent cavities (first cavity, second cavity, third cavity) that can be controlled separately. Each cavity serves specific regions of the airfoil, allowing independent adjustment of cooling in different zones to adapt to varying stagnation point locations while maintaining overall cooling effectiveness.
Solution Approach 2:
The cooling system incorporates movable or adjustable components that can dynamically reconfigure the cooling circuit paths. This allows the system to adapt to changing flow conditions and stagnation point locations caused by variable vane actuation, maintaining optimal cooling effectiveness across different operating conditions.
2Reliability
If cooling circuits are designed to handle large pressure swings, then cooling reliability improves, but device complexity increases due to multicavity design with separate circuits
Solution Approach 1:
The cooling system is segmented into multiple cavities and circuits that can be independently designed and controlled. This segmentation allows each circuit to be optimized for specific pressure conditions, improving overall reliability while managing complexity through modular design that can be implemented incrementally.
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 solution provides increased engine efficiency and maintains cooling effectiveness despite changes in stagnation point position and external pressures, ensuring high convective efficiency and preventing hot gas ingestion across the leading edge of the airfoil.
Implementation Method 1
A first cooling circuit includes a first cavity and a plurality of first film holes. A second cooling circuit includes a second cavity and a plurality of second film holes. A third cooling circuit includes a third cavity and a plurality of third film holes.
Implementation Method 2
The solution provides increased engine efficiency and maintains cooling effectiveness despite changes in stagnation point position and external pressures, ensuring high convective efficiency
Data Source
Figure 1
Figure 2
Figure 3
AI summary
A gas turbine engine component includes an airfoil (72) having a leading edge area (100), a first circuit to cool a first section of the leading edge area (100), and a second circuit to cool a second section of the leading edge area (100). The first circuit is separate and distinct from the second circuit within the airfoil (72). A gas turbine engine (10) comprising variable vanes array (60) upstream of such airfoils (72). A corresponding method of cooling such an airfoil (72).