What is the function of the compressor in a gas turbine?

• A. Increase air pressure and density; prepare air for combustion.
• B. Produce electricity.
• C. Cool the exhaust.
• D. Spin the turbine via thermal energy.

Answer: (C)

Compressing the incoming air is the key job of the compressor: it raises the air’s pressure and density so that more air can be burned efficiently in the combustor. Higher pressure means more air mass in the combustor for a given volume, which allows more fuel to be burned and converts more fuel energy into usable work. This pressure also helps overcome losses in the combustion chamber and supports stable flame conditions. The compression process does heat the air somewhat, but the primary outcome is increased pressure and density to enable efficient and powerful combustion. After compression, the air goes on to the combustor where fuel is injected and burned, creating high-energy gases that drive the turbine. Electricity is generated by the generator connected to the turbine, not by the compressor, and cooling the exhaust is not a function of the compressor.