What is the purpose of inlet air cooling for a gas turbine engine?
Inlet air cooling makes the air denser. Since the compressor of the gas turbine moves a fixed volume of air, the mass flow increases then the air is denser. More mass flow means more power output and improved efficiency. Cooler air also takes less work to compress, so the compressor consumes less of the power produced by the expansion turbine making more power available at the output shaft of the turbine.