Recent research has focused on engine combustion technology as
well as application of after-treatment in order to comply with
emission regulation. However, it is much more efficient way to
control emissions from engine itself and furthermore research on
engine control will provide the direction of after-treatment
technology in future. Furthermore, emission standard regulation for
passenger diesel vehicles has been stringent compared to others and
nano-particles will be included in EURO6 regulation in Europe and
similar emission standard will be introduced in Korea.
A 3.0-liter high-speed diesel engine equipped with by CRDI
system of 160 MPa injection pressure, and an intake/exhaust system
of V type 6-cylinder turbo-intercooler was applied. The conditions
of fuel spray and combustion were investigated by setting up an
ETAS system which is a similar condition to the engine dynamometer
test. The engine drives from an engine speed of 2000 rpm to 3000
rpm to provide 160 MPa high pressure injection by using a piezo
injector. The injection period and injection quantity, pilot
injection types which are related to CRDI and air/fuel ratio
control applied by EVGT were changed simultaneously. In order to
select optimum injection timing, low engine load and injection
quantity were fixed and this experiment was repeated by adjusting
an injection timing driven at maximum high speeds. And then air
excess ratio, cycle change, indicated pressure diagram, heat
release rate and emissions were investigated after injection timing
was selected by MBT.
Standard experiment procedure constituted dilution apparatus and
CPC system to collect nano-particles and these test results were
compared with regulated materials of CO, HC, NOx and
investigated their relation and characteristics of
nano-particles.