Scope for further development
The country among other things has seen an
enormous development in engines used in cars
The Diesel engines have also undergone a sea
change from the time Rudolf Diesel invented it
way back in 1892.
Today Common Rail Direct Injection (CRDI) is
the order of the day.
Unlike in conventional diesel engines, the fuel
is fed into the common tube or rail and high
pressure is maintained.
This allows fuel to combine with air much
It features high-pressure fuel rail feeding
individual solenoid valves as opposed to low-
pressure fuel pump feeding injectors.
Solenoid valves make possible fine electronic
control over the injection time and amount,
and the higher pressure that the common rail
technology makes available provides better
fuel atomization. In order to lower engine
noise, the engine's electronic control unit can
inject a small amount of diesel just before the
main injection event ("pilot" injection), thus
reducing its explosiveness and vibration, as
well as optimizing injection timing and the
Spiral-shaped intake port
Air flow metering
Multiple Pilot injection and
Reduced noise levels
A fuel injector is
nothing but an
swirl and even
distribution of fuel.
Integrated port is used for exhaust gas
recycling. There are three advantages to this
• eliminates external pipes which are subject
• quicker engine warm-up
• better combustion.
It gives exact analysis of the air-mass that is
being taken in.
Due to this metering system, the
microcomputer that controls engine timing
receives precise data.
Pilot injections is small doses of fuel made
prior to the main injection which help to
smoothen the sharp combustion character.
Post injection is a similarly small dose of fuel
injected after the main injection to reduce
The microcomputer regulates the amount of
time the valves stay open and thus the amount
of fuel injected, depending on operating
conditions and how much output is needed.
Besides electronically-controlled exhaust-gas
recycling which contributes to lower nitrous
oxide emissions, CRDI engines are equipped
with catalytic converters near the motor and
emission control devices on the underbody.
These vouch for a high degree of efficiency.
The Electronic control and multiple injections
reduced noise to a great extent.
Use of different fuels for zero emissions and
better engine performance
By using different fuels and cetane improvers,
maximum torque can be obtained
Lowering the cost
Closed-loop control injection with ion sensing
-More power is developed
-Increased fuel efficiency
-Pollutants are reduced
-Particulates of exhaust are reduced
-Exhaust gas recirculation is enhanced
-Precise injection timing is obtained
-Pilot and post injection increase the combustion
-The powerful microcomputer makes the whole
system more perfect
CRDI technology revolutionized diesel engines.
It has changed the way one looks as diesel cars
by providing the above said advantages.
The car makers refer to their common rail
engines by their own brand names. Some of
Hyundai-Kia's CRDi etc
Automotive Mechanics by S Srinivasan..
I C Engines by V. Ganesan.
Automotive Engines by S Srinivasan.
International Journal of Automotive Technology
Approaches to Automotive Emissions Control
Magazines: Auto week, Automobile India