PRIN. OF INTERNAL COMBUSTION ENGINES - OD1619 LESSON 1/TASK 1
in figure 11.
Instead of placing the intake and exhaust ports in the combustion
chamber, they are placed in the cylinder wall.
In this engine, the piston goes
through a power stroke every time it moves from top dead center to bottom dead
center.
As the
piston moves from bottom dead center back to top dead center, it is going through a
compression stroke.
FIGURE 11.
TWO STROKE CYCLE ENGINE.
(a) Downward Stroke (figure 12, view A, on the following page).
The piston
begins the power stroke at top dead center. As the exploding fuel and air mixture
pushes the piston downward, it first covers the inlet port.
This seals the
As the piston continues downward, it uncovers the intake and the
exhaust ports.
The pressure built up in the crankcase forces the fuel and air
mixture into the cylinder through the intake port. The top of the piston is shaped
to divert the mixture upward and away from the exhaust port. As the mixture enters
the cylinder, it displaces and pushes the burnt gases out through the exhaust port.
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