2. Air intake system consists of:
• Air cleaner
• Inlet manifold
• Turbocharger/Supercharger
Functions:
• Supplies oxygen to the cylinders so fuel
will burn.
• Provides for spent gas discharge.
INTRODUCTION
3. • Dry Air is composed of 78% nitrogen and 21% oxygen by
volume.
• Nitrogen is an inactive element.
• At higher altitudes, the air is thinner and under less
pressure, but the nitrogen/oxygen ratio stays the same.
• The air should be clean to remove dust and other
harmful particles.
• The filter is usually located where the air enters the
piping.
AIR SYSTEM
4. • Wet type - Oil bath air cleaner
• Dry type - Paper type air cleaner
• Pre cleaner- Used for all such machines working in very
dusty conditions such as heavy earth moving machines
TYPES OF AIR CLEANERS
5. • It should distribute air–fuel mixture properly.
• It should supply equal amount of charge to each cylinder.
• It should maintain the proportion of air–fuel mixture
properly.
INTAKE MANIFOLD FUNCTIONS
6. • There should be no restriction to charge movement.
• It should give equal charge even to far off cylinder from
the air supply.
• It should not allow charge to condense in it.
• It accommodates air cleaner.
INTAKE MANIFOLD FUNCTIONS
7. • Installed in the pre combustion chamber of the cylinder
head.
• Turned on with the ignition switch.
• Glow plug heats the fuel and air mixture.
• Along with heat generated by compression it allows the fuel
to ignite.
GLOW PLUG
8. • The naturally aspirated system depends on atmospheric
pressure.
• The turbocharger is designed to force air into the
cylinder.
• It uses the energy of exhaust gases to drive a turbine.
• Turbine shaft rotates the compressor wheel.
• Compressed air is forced into the intake manifold.
TURBOCHARGER
10. • The air cleaner must remove fine materials such as
sand, dust, or lint.
• Reservoir large enough to hold material taken out
of the air.
• Types- pre cleaners, dry air cleaners, dry element
air cleaners, and oil bath air cleaners
AIR CLEANERS
11. • Remove large particles of dirt or other foreign matter.
• Cleans air before it enters the main air cleaner.
• Relieves most of the load on the air cleaner.
• Installed at the end of inlet pipe.
PRE-CLEANERS
12. • Used where demand for air is small.
• Cleans the air by passing it through layers of cloth or felt.
• Most common- cleaner with an unloading valve and a
cleaner with a dust cup.
DRY ELEMENT AIR CLEANER
13. • Dry air cleaners are built for two-stage cleaning: pre-
cleaning and filtering.
• By centrifugal action dirt is collected into the dust
unloader valve/dust cap.
• Filtering is performed as the air passes through the
paper filter that filters small particles.
• Pre-cleaners remove over 80 percent of the dirt particles.
DRY ELEMENT AIR CLEANER
14. • Draws air down a center tube where it strikes the surface
of oil.
• The dirt particles gets trapped in the oil.
• The air continues upward and passes to the filter
element.
• The smaller particles that bypassed the oil are trapped.
• The air keeps the filter element soaked with oil.
OIL BATH CLEANERS
16. • Re-circulates a portion of exhaust gas back to engine
cylinders.
• Reduces peak in cylinder temperatures.
• NOx is produced at high temperatures.
• Reduces Nox in emission.
• Utilises part of heat lost into exhaust gases.
EXHAUST GAS RECIRCULATION
