Leachable Casting Core Tie Bars for Gas Turbine Cooling Passage Isolation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In gas turbine engine manufacturing, the casting process for creating cooling passages often results in 'cross talk' or 'kiss out' due to shifting core legs, leading to undesirable linking cavities that disrupt fluid flow, necessitating additional tie bars for support which also create unwanted fluid pathways.
Innovation Solution
A leachable casting core with strategically designed tie bars that obstruct fluid communication through linking cavities, utilizing various aerodynamic and structural concepts such as obstructions, pressure balancing, and coil configurations to minimize fluid flow through these cavities.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If tie bars are used to secure core legs in position, then manufacturing reliability is improved, but linking cavities are created that allow unwanted fluid communication between cooling passages
Solution Approach 1:
The patent converts the harmful linking cavities created by tie bars into beneficial flow obstructions by designing the tie bars with bends, coils, or irregular configurations. These modified tie bars still secure the core legs but create flow resistance that prevents unwanted fluid communication between cooling passages, effectively turning the harmful cavities into useful flow control features.
Solution Approach 2:
The patent applies different properties to different parts of the tie bar structure. The tie bars have securement functions at their connection points to core legs while having flow-obstructing configurations (bends, coils, irregular shapes) in their intermediate sections. This local differentiation allows the same component to simultaneously provide structural support and fluid flow control.
2Ease of manufacture
If traditional straight tie bars are used, then manufacturing simplicity is maintained, but fluid flow through linking cavities is excessive
Solution Approach 1:
The patent replaces straight tie bars with bent, coiled, or irregularly shaped tie bars. These curved configurations increase the path length and flow resistance of linking cavities, reducing unwanted fluid communication between cooling passages while still maintaining structural support functionality.
Solution Approach 2:
The tie bar configurations are designed to create dynamic flow resistance rather than simple open cavities. The bends and coils in the tie bars create tortuous flow paths that increase resistance to fluid communication, effectively controlling the flow dynamics through the linking cavities.
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 effectively reduces fluid flow through linking cavities by up to 50% compared to traditional designs, improving the producibility and efficiency of cooling passages in gas turbine components.
Implementation Method 1
a core within the cast body and comprising a second material that is susceptible to leaching
Data Source
AI summary
A cast component having reduced cross flow linking cavities and method of casting may include a body. The body may define a plurality of internal flow channels. The plurality of internal flow channels may include a first internal flow channel and a second internal flow channel. The cast component may also include a plurality of linking cavities obstructing unintended fluid communication between the first internal flow channel and the second internal flow channel through the plurality of linking cavities.