Which component is hottest in a gas turbine engine?

• A. The nozzle guide vanes
• B. The turbines
• C. The combustion chamber
• D. The compressor

Answer: (B)

In a gas turbine, the hottest heat load on the components comes from the hot gases that form after combustion and flow straight into the turbine. The combustor does reach very high flame temperatures, but its walls are designed and cooled to keep the metal temperatures manageable. The turbine blades and vanes sit directly in that hottest gas stream and must extract energy from it while withstanding a very high heat flux. Even though cooling air and coatings protect them, the turbine section endures the greatest thermal stress, so it is the hottest component overall.