How is the HP turbine rotor of the GE LM2500 gas turbine engine cooled?

Correct Answer: Option D — By a continuous flow of compressor discharge air

High-pressure turbine rotors operate in extreme temperatures exceeding the melting point of the blade alloys. To maintain structural integrity, a continuous flow of compressor discharge air is bled from the compressor and directed through internal cooling passages in the turbine blades, providing necessary convective and film cooling.