International Research Journal of Engineering and Technology (IRJET) e-ISSN: 2395 -0056
Volume: 04 Issue: 04 | Apr -2017 www.irjet.net p-ISSN: 2395-0072
© 2017, IRJET | Impact Factor value: 5.181 | ISO 9001:2008 Certified Journal | Page 3012
Investigation of emission parameters on HCCI Engine using chemical
kinetics
D Bhaskar
1
, J Naveen Reddy
2
, Ch Sai Siva Reddy
3
, M Pavan
4
, J Shreenath
5
1
Assistant Professor, Mechanical Engineering Dept., K L University
2345
Final Year B-tech, Mechanical Engineering Dept., K L University
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Abstract - Homogeneous Charge Compression Ignition
makes the utilization of the resources for complete
combustion and is similar to that of hot bulb technology. In
these, the main point is to supply the exact mixture of fuel and
oxidizer to the combustion chamber to attain auto ignition.
The characteristics of these technology resemble the
combination of both spark and compression ignition Engine.
The Engine which result in these combination provide higher
efficiencies better than the conventional Engines. Diesel as the
fuel and performing computation results by using CHEMKIN
17.0 with HCCI Engine parameters that are previously done on
the experimental scale provides the liability for further
investigation on different compositions to find reduced
emission rates by performing auto ignition. Spectroscopy
methods provides the necessary species that provides auto
ignition. The species responsible for these condition are HO2,
CH2O and O. Formation of these species can be visualized in
the fuel combustion kinetics provided by CHEMKIN 17.0.
Emission rates on diesel are compared by varying fuel grades
and equivalence ratio.
Keywords: Engine, HCCI, Auto ignition, Emission,
Chemical kinetics.
1. INTRODUCTION
Compression ignition Engine with its
thermodynamic efficiency and lower pumping loses
add an advantage to continue the usage in the
commercial sector for a long time. While spark ignition
Engine, due to its low emissions at exhaust gives
additional benefit for environmental issues because of
homogeneous mixture fuel and air. In these new
technology which combines these two types is called as
Homogeneous Charge Compression Ignition as the
name indicates, in this HCCI Engine technology has SI
Engine characteristics at inlet and compression strokes
and has CI Engine characteristics at combustion and
exhaust strokes. This technology results us in getting
higher fuel efficiency and low emissions. HCCI Engine
can be accepted over conventional Engines because of
its performance, durable, sustainable and economical.
Homogeneous Charge Compression Ignition reduce
throttling losses. It meets the standards that are to be
followed for emissions. Any alternate fuels and the
conventional fuels can be used for the operation. As
expansion ratio is increased using HCCI Engine results
in increased thermodynamic efficiency than the
conventional Engine. Emission can be controlled
without the application of EGR system. In HCCI at
normal compression ratio only the auto-ignition occurs
and load limit can be extended which reduce the
residuals in the fuel mixture to achieve the starting
temperature of compression, mode of combustion as
they are to be maintained in limits.
HCCI Engine combustion should be started after the
auto ignition where the ignition timing can’t be
controlled in practical because there will be variations
in speed and power range. This leads to increase in
emissions of HC and CO but reduction in NOx and SOx
emissions. Pre-heating is done in order to provide
additional energy to attain required auto ignition
temperature to the in-cylinder load. Negative valve
overlap is used for pre-heating but it is limited to low,
medium loads only. Higher exhaust re-circulated will
allow higher thermal loads because there will be