Turbine Rotor Drum Cooling via Exhaust Gas Self-Service

The patent utilizes the turbine's own exhaust gases to provide secondary flow cooling at the rotor drum, rather than extracting cold air from the compressor. The exhaust gases are directed through passages in the rotor drum to cool the secondary flow surfaces, allowing the system to serve its own cooling needs without external air consumption, thereby improving fuel burn and propulsive efficiency

The patent recovers waste heat from the turbine exhaust gases and repurposes them for cooling the rotor drum secondary flows. Instead of discarding the hot exhaust gases directly to the atmosphere, they are routed through cooling passages to extract heat from the rotor drum surfaces, converting a waste resource into a useful cooling function and reducing the need for additional compressor air

The exhaust gas cooling system is integrated directly into the rotor drum structure with internal passages that allow exhaust gases to flow through and cool the drum surfaces. This self-contained approach provides clearance control without requiring external air supply systems or additional heavy components, achieving precise clearance control while minimizing engine weight

The rotor drum structure serves multiple functions: it acts as the rotating component of the turbine, contains the secondary flow passages for cooling, and integrates the exhaust gas routing system. This multi-functionality eliminates the need for separate clearance control systems that would add weight, as the same structural elements perform both mechanical and thermal management functions