8.12.2 ADVANTAGE OF SUPERCHARGING
Due to a number of advantages of supercharging the modern diesel engines used in diesel plants
are generally supercharged. The various advantages of supercharging are as follows:
1. Power Increase. Mean effective pressure of the engine can be easily increased by 30 to 50%
by supercharging which will result in the increase the power output.
2. Fuel Economy. Due to better combustion because of increased turbulence, better mixing of
the fuel and air, and of an increased mechanical efficiency, the specific fuel consumption in most cases,
though supercharging reduces not all.
3. Mechanical Efficiency. The mechanical efficiency referred to maximum load is increased
since the increase of frictional losses with a supercharger driven directly from the engine is quite smaller
as compared to the power gained by supercharging.
4. Fuel Knock. It is decreased due to increased compression pressure because increasing the
inlet pressure decreases the ignition lag and this reduces the rate of pressure rise in the cylinder resulting
in increasing smoothness of operation.
5. Volumetric Efficiency. Volumetric efficiency is increased since the clearance gases are compressed
by the induced charge that is at a higher pressure than the exhaust pressure.