The use of diesel engines for vehicle has been increasing recently due to its
higher thermal efficiency and lower CO2 emission level. However, in the case
of diesel engine, NOx increases in a high temperature combustion region and
particulate matter is generated in a fuel rich region. Therefore, the
technique of PCCI (premixed charge compression ignition) is often studied to
get the peak combustion temperature down and to make a better air-fuel
mixing. However it also has got a limited operating range and lower engine
power produced by the wall wetting and the difficulty of the ignition timing
control. In this research, the effect of injection strategies on the
injected fuel behavior, combustion and emission characteristics in a PCCI
engine were investigated to find out the optimal conditions for fuel
injection, and then ethanol blended diesel fuel was used to control the
ignition timing. As a result, the combustion pressures and ROHR (rate of
heat release) of the blended fuel became lower, however, IMEP showed fewer
differences. Especially in the case of triple injection, smoke could be
reduced a little and NOx emission decreased a lot by using the ethanol
blended fuel simultaneously without much decreasing of IMEP compared to the
result of 100% diesel fuel.
Effects of ethanol added fuel on exhaust emissions and combustion in a premixed charge compression ignition diesel engine
