Combustion Chamber Design

Principles of Internal Combustion Engines
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a. General. The fuel injected into the combustion chamber must be mixed

thoroughly with the compressed air and be distributed as evenly as possible

throughout the chamber if the engine is to function at maximum driveability. The

welldesigned diesel engine uses a combustion chamber that is designed for the

engine's intended usage. The injectors used in the engine should compliment the

combustion chamber. The combustion chambers described in the following

subparagraphs are the most common and cover virtually all of the designs that are

used in current automotive applications.

b. Open Chamber (figure 34 on the following page). The open chamber is the

simplest form of chamber. It is suitable for slowspeed, four stroke cycle

engines, and is used widely in two stroke cycle diesel engines. In the open

chamber, the fuel is injected directly into the space at the top of the cylinder.

The combustion space, formed by the top of the piston and the cylinder head, is

usually shaped to provide a swirling action of the air as the piston comes up on