Supercharging of IC Engines – It is the process of increasing the mass (or in other words density) of the air fuel mixture (in spark ignition engines) or air (in compression ignition engines) induced into the engine cylinder. This is usually done with the help of a compressor or blower known as supercharger. It has been experimentally found that the supercharging increases the power developed by the engine. It is widely used in aircraft engines, as the mass of air sucked in the engine cylinder decreases at very high altitudes. This happens, because atmospheric pressure decreases with the increase in altitude.

Following are the objects of supercharging the engines :

1.    To reduce mass of the engine per brake power (as required in aircraft engines).

2.    To maintain power of air craft engines at high altitudes where less oxygen is available for combustion.

3.    To reduce space occupied by the engine (as required in marine engines).

4.    To reduce.consumption of lubricating oil (as required is all types of engines).

5.    To increase the power output of an engine when greater power is required (as required in racing cars and other engines).