Ejectors in a Compressible Network for Gas Turbine Extended Operability

Turbine wheel spaces are cooled with air extracted from one of the early compression stages; under partial load the compressor bleed pressure reaches a value slightly lower than that of the turbine wheels, making the cooling ineffective and in the worst case, reverse flow must be avoided. In order to overcome this situation, a solution involving an ejector has been implemented. The motive air, which comes from one of the last compressor stages, is used to avoid a reverse flow into the turbine wheel space through mixing with the air extracted from the early stage