The highest heat to metal contact in a jet engine is the.

• A. Burner cans
• B. Turbine blades
• C. Turbine inlet guide vanes
• D. Nozzle guide vanes

Answer: (C)

The highest heat transfer into metal in the hot section comes where the hottest gas first contacts solid surfaces with minimal cooling protection. The turbine inlet guide vanes sit right at the entry to the turbine and face the hottest combustion gases directly. They are stationary and typically have less aggressive cooling compared to the rotating blades, which are protected by internal cooling passages and film cooling. The blades do see very hot gas too, but the cooling they receive keeps the actual metal temperature lower than that of the inlet guide vanes. Burner cans and nozzle guide vanes are also in the hot path, but their cooling arrangements and positions generally result in less heat transfer to the metal than the turbine inlet guide vanes. So, the turbine inlet guide vanes experience the greatest heat-to-metal contact.