Analysis of combustion in DI Diesel engine

In internal combustion engines combustion takes place within the engine cylinder. IC Engines are classified as two stroke and four stroke engines. Four stroke DI (Direct Injection) Diesel engine is an engine in which diesel is used as a fuel to produce power and the operation of the engine is completed in four strokes of piston and two revolutions of crankshaft. Basically there are four strokes in an DI Diesel engine i.e. suction of only atmospheric air compression of air at just the end of the compression stroke when piston reaches before the top dead centre (TDC) the fuel (Diesel) is injected. The compressed air and injected fuel causes combustion inside the engine cylinder known as combustion chamber. Due to combustion the gases inside the combustion chamber expands that belongs to the expansion stroke. And finally the products of combustion are expelled to atmosphere that is the exhaust stroke.