PORT TIMING DIAGRAM FOR TWO STROKE C.I ENGINE

The port timing diagram for two stroke C.I Engine is exactly similar to the two stroke cycle S.I Engine except the position of opening and closing of fuel valve. Fuel is injected into the cylinder 10* to 15* before TDC.

Fuel Injection continues till 15* to 20* after TDC. The Other difference between these two is, the charging and scavenging period of CI. engine (90*) is greater than the S.I Engine (70*)

Since, There is no danger of loss of fuel during scavenging of diesel engine as only air is charged.

PORT TIMING AND EVENTS DURING PORT TIMING :

IPO - IPC Air is sucked into the crankcase through plate valve.

IPC - TPO Air is compressed partially in the crankcase. ( Crankcase compression ).

TPO - TPC Partially compressed air is transferred to the engine cylinder through transfer port.

TPC - FIB Air is compressed in the cylinder, Both the pressure and temperature of the air increase.

FIB - FIC Fuel is Injected into the hot compressed air. Fuel mixes with hot air and burns.

FIC - EPO The burning gases expand and move the piston to do work.

EPO - EPC Burnt gases escape to the atmosphere through exhaust port.

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Mechinopedia For Mechanical Engineers

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