A gas-turbine engine is a thermodynamic machine that converts the chemical energy stored in a fuel into mechanical work through the controlled expansion of hot gases. Its operation generally consists of three main sections: a compressor, which increases the pressure of an ingested fluid; a combustor, which mixes the pressurized fluid with a fuel and rapidly combusts it to significantly raise the temperature and volume; and a turbine, which captures the energy from the resulting high-velocity, high-temperature exhaust flow. This expansion drives the turbine blades, causing a shaft to rotate, and the turbine is typically mechanically coupled to the compressor or a generator to produce usable power.