In the marine gas turbine engine shown in the illustration, the 13th stage bleed air is used for __________. Illustration GT-0017

Correct Answer: Option D — high pressure turbine 2nd stage nozzle cooling

Thirteenth-stage compressor bleed air is utilized for cooling the high-pressure turbine (HPT) second-stage nozzle vanes. This high-pressure air is directed through internal passages to manage the thermal load on the nozzle guide vanes, ensuring they operate within metallurgical limits despite extreme combustion temperatures.