Spherical Combustion Chamber.

Principles of Gasoline And Diesel Fuel Systems
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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 the chamber. This turbulence speed is

approximately 50 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.

d. Spherical Combustion Chamber.

The spherical combustion chamber is

designed principally for use in the multifuel engine. The 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 which produces a swirling effect on

the intake air as it enters the chamber.

Operation of the chamber is as

follows:

(1) As the air enters the combustion chamber, a swirl effect is

introduced to it by the shape of the intake port (figure 42, view A, on the

following page).

(2) During the compression stroke, the swirling motion of the air

continues as the temperature in the chamber increases (figure 42, view B, on

the following page).

(3) As the fuel is injected, approximately 95 percent of it is

deposited on the head of the piston and the remainder mixes with the air in

the spherical combustion chamber (figure 42, view C, on the following page).

(4) As combustion begins, the main portion of the fuel is swept off

of the piston head by the high velocity swirl that was created by the intake

and the compression strokes. As the fuel is swept off of the head, it burns

through the power stroke, maintaining even combustion and eliminating

detonation (figure 42, view D and E, on the following page).