Question 84Gas Turbine - 1st Asst/Chief

The correct answer is D) all of the above. The air shroud (swirl cup) around the fuel nozzle tip of a GE LM2500 gas turbine engine serves multiple purposes: 1. It helps to cool the nozzle tip, preventing excessive heating and potential coking or clogging of the nozzle. 2. It promotes air turbulence around the nozzle, which enhances the air/fuel mixing for more efficient combustion. 3. The combination of cooling and air turbulence helps to atomize the fuel and promote a better air/fuel mixture, leading to more complete and efficient combustion. The other answer choices, while addressing individual aspects, do not capture the full, multi-purpose function of the air shroud design.