• Functions of Combustion Chamber
• Classification of Combustion Chamber
• Combustion Chambers in S.I. Engines
• Combustion Chambers in C.I. Engines
• A Combustion chamber is an
important component of an Internal
combustion engine in which the
chemical energy of the fuel is
converted into mechanical energy
to power the vehicle or machinery.
4. Functions of Combustion Chamber
• It houses the inlet & outlet valve for incoming and outgoing of mixture
• It houses and guides the piston
• It helps in proper combustion by proper geometry
• It withstands against the high temperature of combustion
• It prevents to spill out the exhaust of combustion
5. Requirements for Good Combustion Chamber
• A good combustion chamber can deliver High Power Output
• and High Thermal Efficiency.
• Smooth Engine Operation
• Long Engine life
• Avoid knocking and detonation
• Reduce exhaust pollutants.
6. Combustion Chamber
in SI Engines
T - Head Type
L - Head Type
I - Head Type
F - Head Type
in CI Engines
Indirect Injection Type
8. T – Head Type Combustion Chamber
• It is the earliest used type of combustion
• This was introduced by Ford in 1908.
• In this type, the valves are located on
opposite sides of the cylinder head,
forming a T shape & the spark plug is
located in the cylinder head.
• As the valves are placed on either side,
they require individual camshafts to
9. L – Head Type Combustion Chamber
• This type was used by Ford between 1910
• This type of combustion chamber was
developed to overcome the disadvantage
of T-head type combustion chambers.
• In this type, the inlet & exhaust valves are
placed on the same side and thus they can
be operated by single camshaft.
• It has a simple valve mechanism which
results in easy maintenance and
Top View of Cylinder Head
10. I – Head Type Combustion Chamber
• This was first developed by Buick and it
has been in use since the 1950s.
• In this type both the valves are mounted on
head of the cylinder.
• Hence this is also known as overhead
• The valves at the top provide direct
passage for the fuel which makes it more
Inside Top View of Cylinder Head
11. I – Head Type Combustion Chambers
Bath Tub Type
In the bath tub type, spark plug is placed at
the side and the valves are placed vertically at
In the wedge type, the valves are placed
inclined, whereas the spark plug is placed at
12. F – Head Type Combustion Chamber
• This type is the intermediate between the L
and I type head combustion chambers.
• It has an inlet valve at the cylinder head
similar to the I-head type
• and exhaust valve on the cylinder block
similar to the L-head type.
• The F-head chamber was successfully
used by Rover Company and in Willy’s
15. Open or Direct Injection (DI) Combustion
• In an open combustion chamber the space
between the piston and cylinder head is open
i.e. there is no restriction in between.
• The fuel is injected directly into the combustion
chamber that’s why it is known as Direct
Injection Combustion Chamber
• Advantages :
Simpler in design
High power output
• Disadvantages :
Produces more emissions
17. Indirect Injection (IDI) Combustion Chamber
• In an indirect injection combustion chamber, the
fuel is injected into a small pre-chamber or swirl
chamber, which is connected to the main
combustion chamber. The fuel is ignited in the
pre-chamber, which then ignites the mixture in
the main combustion chamber.
Produces lower emissions
• Disadvantages :
Complex manufacturing processes
18. Pre Combustion Chamber
• A pre-combustion chamber is a type
of indirect injection combustion
chamber where the air and fuel are
introduced into a small separate
chamber, which is connected to the
main combustion chamber by a
small hole called orifice.
• It allows for better mixing of the air
and fuel, which leads to improved
19. Swirl Combustion Chamber
• These combustion chambers are
similar as that of pre-combustion
• The difference is that in pre-
combustion chamber only 20 to
25% of total air enters while in this
type 80 to 90% total air circulates in
• As high rate of “swirl” is produced in
this type, it is known as swirl
20. Air–Cell Combustion Chamber
• In this chamber, the clearance volume is divided into
two parts, one in the main cylinder and the other called
the energy cell.
• The energy cell is divided into two parts, major and
minor, which are separated from each other and from
the main chamber.
• In this combustion chamber the fuel is injected in the
main chamber while in the other case into pre-
• The fuel is forced at high velocity from the main
chamber into the neck of energy-cell where the
combustion is initiated and due to high pressure rise it
flows back into main chamber.
• This high velocity jet produces swirling motion in the
main chamber and thereby thoroughly mixes the fuel
with air resulting in complete combustion
• This combustion chamber is suitable only for constant
In other words, the volume or confined space between the piston head (at Top Dead Center) and cylinder head in an Internal Combustion engine where the air-fuel mixture is ignited or burnt is called Combustion Chamber.
A camshaft is a mechanical component in an engine that controls the opening and closing of the engine’s valves.