2 stroke cycle diesel engine

. Two-Stroke Cycle Diesel Engine A two-stroke diesel engine shares the same  operating  principles  as  other  internal  combustion engines. It has all of the advantages that other diesel engines have over gasoline engines. A two-stroke diesel engine does not produce as much power as a four-stroke diesel engine; however, it runs  smoother  than  the  four-stroke  diesel.  This  is because it generates a power stroke each time the piston moves downward; that is, once for each crankshaft revolution. The two-stroke diesel engine has a less complicated valve train because it does not use intake valves. Instead, it requires a supercharger to force air into the cylinder and force exhaust gases out, because the piston cannot do this naturally as in four-stroke engines.  

The  two-stroke  diesel  takes  in  air  and  discharges exhaust  through  a  system  called  scavenging. Scavenging  begins  with  the  piston  at  bottom  dead center. At this point, the intake ports are uncovered in the cylinder wall and the exhaust valve is open. The supercharger forces air into the cylinder, and, as the air is  forced  in,  the  burned  gases  from  the  previous operating cycle are forced out.

  COMPRESSION   STROKE.—   As  the  piston moves towards top dead center, it covers the intake ports. The exhaust valves close at this point and seals the upper cylinder. As the piston continues upward, the air in the cylinder is tightly compressed . As in  the  four-stroke  cycle  diesel,  a  tremendous  amount  of heat is generated by the compression.

  POWER STROKE.— As the piston reaches top dead  center,  the  compression  stroke  ends.  Fuel  is injected  at  this  point  and  the  intense  heat  of  the compression causes the fuel to ignite. The burning fuel pushes the piston down, giving power to the crankshaft. The power stroke ends when the piston gets down to the point where the intake ports are uncovered. At about this point, the exhaust valve opens and scavenging begins again

. Valve  Train The operation of the valves in a timed sequence is critical. If the exhaust valve opened in the middle of the intake stroke, the piston would draw burnt gases into the combustion chamber with a fresh mixture of fuel and air. As the piston continued to the power stroke, there would be nothing in the combustion chamber that would