Industrial gas turbines from MAN Diesel & Turbo cover the 7 -13 MW range. This animation explains the working principle of these heavy duty machines by example of the new MGT series.
source/image: MAN Energy Solutions
A twin shaft version serves for mechanical drive applications while the design of the single shaft version is dedicated for power generation. You’ll see some basic similarities to jet engines.
The basic operation of the gas turbine is a Brayton cycle with air as the working fluid. Atmospheric air flows through the compressor that brings it to higher pressure. Energy is then added by spraying fuel into the air and igniting it so the combustion generates a high-temperature flow.
This high-temperature high-pressure gas enters a turbine, where it expands down to the exhaust pressure, producing a shaft work output in the process.The turbine shaft work is used to drive the compressor; the energy that is not used for compressing the working fluid comes out in the exhaust gases that can be used to do external work, such as directly producing thrust in a turbojet engine, or rotating a second, independent turbine (known as a power turbine) which can be connected to a fan, propeller, or electrical generator./wikipedia