The modern day Gas turbine engines are usually cylindrical in shape and
they have the necessary parts inside the engine in longitudinal way, the main
components we will come across from front to rear end are usually as follows:
- Compressor
- Combustion system
- Turbine assembly
- Exhaust system
A shaft connects the turbine to the compressor which
creates the engine to rotate by using the gas reaction and generate the axial
flow. Fuel burners are positioned in the combustion system. Initial
ignition is provided once the air flow is produced by rotation of the
compressor, the pressure of the mass ensures the expanding gas in the
combustion chamber travels in a rearward direction. Once ignition is achieved,
the flame will be continuous, and the ignition device can be switched
off. The hot gases crossing the turbine produce torque to drive the
compressor, therefore the starter can also be switched off. This is usually
known as self-sustaining speed of the engine.
In
the past the all the sections in compressor was one single unit and
turbine was one single unit. these two were attached using a spool or
shaft. however, now days the engines can provide high thrust for the
aircraft and the engine has made in different sections which allows
rotation of the compressor stages if different speeds to get optium
results. This kind of engines are named as multi spool engines which has
2- 3 shafts connecting different sections of turbines to matching
compressor sections. usually they are termed as Low pressure Compressors / Low pressure Turbines and High pressure compressors/ High pressure turbines.
