PRIN. OF INTERNAL COMBUSTION ENGINES - OD1619 LESSON 1/TASK 2
turbulence chamber during the compression stroke.
The chamber usually is
spherical, and the opening through which the air must pass becomes smaller as the
piston reaches the top of the stroke, thereby increasing the velocity of the air in
This turbulence speed is approximately 60 times crankshaft speed.
The fuel injection is timed to occur when the turbulence in the chamber is the
greatest. This ensures a thorough mixing of the fuel and the air, with the result
that the greater part of combustion takes place in the turbulence chamber itself.
The pressure created by the expansion of the burning gases is the force that drives
the piston downward on the power stroke.
e. Spherical Combustion Chamber (figure 37 on the following page). The spherical
chamber consists of a basic open-type chamber with a spherical-shaped relief in the
top of the piston head.
The chamber works in conjunction with a strategically
positioned injector and an intake port that produces a swirling effect on the
intake air as it enters the chamber. Operation of the chamber is as follows: