Gas Turbine Angelwing Cooling Passage Design

The cooling system is segmented into multiple independent cooling passages (first cooling passage, second cooling passage, third cooling passage) that distribute cooling air to specific locations. This segmentation allows targeted cooling of the angelwing and buffer cavity region without requiring excessive cooling air volume, thereby protecting components while minimizing impact on engine efficiency.

The angelwing structure serves as an intermediary element between the inner wheelspace and outer rotor/stator cavity. By incorporating cooling passages within the angelwing itself, the system uses this intermediate structure to deliver cooling air directly to critical regions, preventing hot gas ingestion without requiring large volumes of cooling air that would reduce engine efficiency.

Cooling air is supplied in advance through the first cooling passage to the upper surface of the angelwing before hot combustion gases can cause excessive temperature rise. This preliminary cooling action maintains the angelwing surface temperature within acceptable limits, preventing creep-related failure while preserving component strength.

The system uses pressurized cooling air delivered through pneumatic cooling passages (first, second, and third cooling passages) to cool the angelwing surfaces. The pressurized air flow through these passages effectively removes heat from the angelwing upper surfaces that are exposed to hot combustion gases, maintaining structural integrity by preventing temperature-induced creep failure.

The angelwing structure is designed with multiple cooling passages that serve multiple functions: the first cooling passage cools the upper surface, the second cooling passage cools the buffer cavity region, and the third cooling passage provides additional cooling. This multi-functional design allows a single structural element (the angelwing) to perform both structural support and thermal management functions, improving temperature control without proportionally increasing device complexity.

The cooling passages are nested within the angelwing structure itself, with the first, second, and third cooling passages integrated into the angelwing's geometry. This nesting approach allows multiple cooling functions to be incorporated within the existing structural framework, improving temperature control while minimizing the increase in device complexity by utilizing the angelwing's own volume for housing the cooling passages.