Which statement best describes the order of engine stations in the mass airflow path?

• A. Inlet, diffuser, compressor, burner, turbine, exhaust.
• B. Inlet, compressor, burner, diffuser, turbine, exhaust.
• C. Inlet, compressor, diffuser, burner, turbine, exhaust.
• D. Inlet, burner, diffuser, compressor, turbine, exhaust.

Answer: (C)

The mass airflow path in a gas turbine follows a specific sequence to prepare air for combustion and to extract useful energy afterward: air enters the inlet, passes through the diffuser to slow it and raise pressure, then goes into the compressor to be further pressurized, enters the burner to support combustion, moves through the turbine where energy is extracted to drive the compressor, and finally exits through the exhaust. The diffuser’s job is to recover pressure and slow the air before it reaches the compressor, which makes the compressor work efficiently and prevents flow instability. After compression, fuel is burned in the burner, heating the gases so the turbine can extract energy and still allow the exhaust to release the high-energy gases.

So the sequence that matches this flow is inlet, diffuser, compressor, burner, turbine, exhaust. Placing the diffuser after the compressor would miss its purpose of slowing and pressurizing the air before compression, and placing the burner before proper compression would hinder stable, efficient combustion.