2 stroke cycle diesel engine

.Two-Stroke Cycle Diesel EngineA two-stroke diesel engine shares thesame  operating  principles  as  other  internal  combustionengines. It has all of the advantages that other dieselengines have over gasoline engines.A two-stroke diesel engine does not produce asmuch power as a four-stroke diesel engine; however, itruns  smoother  than  the  four-stroke  diesel.  This  isbecause it generates a power stroke each time the pistonmoves downward; that is, once for each crankshaftrevolution. The two-stroke diesel engine has a lesscomplicated valve train because it does not use intakevalves. Instead, it requires a supercharger to force airinto the cylinder and force exhaust gases out, becausethe piston cannot do this naturally as in four-strokeengines. 

The  two-stroke  diesel  takes  in  air  and  dischargesexhaust  through  a  system  called  scavenging.Scavenging  begins  with  the  piston  at  bottom  deadcenter. At this point, the intake ports are uncovered inthe cylinder wall and the exhaust valve is open. Thesupercharger forces air into the cylinder, and, as the airis  forced  in,  the  burned  gases  from  the  previousoperating cycle are forced out.

 COMPRESSION   STROKE.—   As  the  pistonmoves towards top dead center, it covers the intakeports. The exhaust valves close at this point and sealsthe upper cylinder. As the piston continues upward, theair in the cylinder is tightly compressed . Asin  the  four-stroke  cycle  diesel,  a  tremendous  amount  ofheat is generated by the compression.

 POWER STROKE.— As the piston reaches topdead  center,  the  compression  stroke  ends.  Fuel  isinjected  at  this  point  and  the  intense  heat  of  thecompression causes the fuel to ignite. The burning fuelpushes the piston down, giving power to the crankshaft.The power stroke ends when the piston gets down to thepoint where the intake ports are uncovered. At about thispoint, the exhaust valve opens and scavenging beginsagain

.Valve  TrainThe operation of the valves in a timed sequence iscritical. If the exhaust valve opened in the middle of theintake stroke, the piston would draw burnt gases into thecombustion chamber with a fresh mixture of fuel andair. As the piston continued to the power stroke, therewould be nothing in the combustion chamber that would