Operation
0060−1/A1
Winterthur Gas & Diesel Ltd.
1/ 1
Two-stroke Diesel Engine − Operation
1. Piston Movement
1.1 First Stroke (Compression)
The sequence of piston movements during the compression stroke is as follows:
D The piston is at BDC (see Fig. 1).
D The scavenge ports and exhaust valve are open.
D Scavenge air flows into the cylinder and pushes the exhaust gas through the
exhaust valve into the exhaust gas manifold and then to the turbocharger.
D The piston moves up.
D At ES, the piston covers the scavenge ports.
D At AS, The exhaust valve closes and compression starts, which heats the air.
1.2 Second Stroke (Ignition − Combustion − Expansion − Exhaust −
Scavenging)
The sequence of piston movements during the second stroke is as follows:
D When the piston is almost at TDC, fuel is injected into the cylinder.
D The fuel ignites in the compressed, heated air and combustion starts.
D The gases expand and push the piston down.
D At AO, the exhaust valve opens. Exhaust gas flows out of the cylinder into the
exhaust gas manifold.
D At EO, the piston continues to move down to let air in through the scavenge
ports.
D Scavenge air flows into the cylinder and pushes the exhaust gas through the
exhaust valve into the exhaust gas manifold and then to the turbocharger.
See also the schematic diagram in 6500−1 Turbocharging.
TDC
BDC
AO
EOES
AS
Fig. 1: Schematic of Engine Operation
2014
General
To Next Page
Loading...
