Ceramic Core with Varying Thickness for Gas Turbine Cooling
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Gas turbine engine parts manufactured through investment casting often require drilling cooling holes post-casting, which is time-consuming and may not fully address the extreme operating conditions, especially under repetitive thermal cycling.
Innovation Solution
A ceramic core with varying thickness and cooling hole forming portions is used in the casting process to create internal cooling circuits with cooling openings that extend through the exterior surface, eliminating the need for post-casting drilling by forming the cooling openings during the casting process.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If cooling holes are drilled into the cast part after casting, then the part can be cooled during operation, but the process is time-consuming and reduces productivity
Solution Approach 1:
The core is pre-formed with cooling hole forming portions that define the cooling openings before the casting process. This preliminary action eliminates the need for post-casting drilling, as the cooling holes are already formed during the casting process itself, thereby reducing the overall manufacturing cycle time while ensuring reliable cooling capability.
Solution Approach 2:
The invention merges the core function with the cooling hole formation function. The core body includes integrated cooling hole forming portions that simultaneously serve as the core structure and the template for creating cooling openings. This combination eliminates separate drilling operations and integrates cooling hole formation into the casting process, improving productivity without compromising cooling reliability.
2Reliability
If a standard thickness core is used, then the manufacturing process is simpler, but the cooling efficiency is insufficient under extreme operating conditions
Solution Approach 1:
The core body features variable thickness with different regions optimized for specific functions: thicker sections provide structural support and stability, while thinner sections facilitate efficient heat transfer and cooling. The cooling hole forming portions have specifically designed geometries with varying cross-sectional areas to optimize coolant flow distribution. This local quality variation enhances cooling efficiency in critical areas without unnecessarily increasing overall core complexity.
Solution Approach 2:
The core structure employs parameter changes in thickness and cooling hole geometry to optimize cooling performance. The cooling hole forming portions include variations in cross-sectional area along their length, with metering sections and diffusing sections that control coolant flow rates. These parameter changes enable the core to deliver enhanced cooling efficiency under extreme operating conditions while maintaining a manageable structural complexity through systematic design.
3Productivity
If cooling openings are formed during casting, then productivity increases, but the core structure becomes more complex
Solution Approach 1:
The core body is segmented into functional zones including the core body itself and distinct cooling hole forming portions. Each cooling hole forming portion is further divided into metering sections and diffusing sections with specific geometries. This segmentation allows the complex cooling hole formation function to be broken down into manageable structural elements that can be systematically manufactured and integrated into the core, reducing overall manufacturing cycle time while controlling core structure complexity through modular design.
Data Source
Figure 1
Figure 2~3
Figure 4~5
AI summary
A core (60) for a casting process includes a core body (68) and a first cooling hole forming portion (70) that extends from the core body (68). The core body (68) includes a varying thickness (T) along a length of the core body (68). The core body (68) can include an undulating shaped section and can be a ceramic core body.