In order to explore the mechanism of EGR on the formation of diesel engine particles, the effects of different EGR rates on the microcrystalline structure and oxidation characteristics of particulate matters were analyzed by means of Raman spectroscopy(Raman) and thermogravimetric analysis(TG). The laws of several parameters were clarified, including the chemical heterogeneity, graphitization degree, average crystallite size, bond length of C—C atoms, and activation energy. The results showed that the width at half of D1 peak increased gradually and the chemical heterogeneity of particulate matters enhanced with the increase of EGR rate. The ratios of ID1/IGand ID3/IG gradually increased, which increased by 12.9% and 12.1% respectively for EGR30%. The ordered graphite structure reduced, the amorphous carbon increased, and the graphitization degree weakened. In addition, the average crystallite size and activation energy of particulate matters both decreased. The activation energy of EGR30% decreased by 3.6%, which indicated that EGR could improve the oxidation activity of particulate matters.
QU Lei
,
WANG Zhong
,
LIU Shuai
,
XIE Weian
. Influence of EGR Rate on Microcrystalline Structure and Oxidation Characteristics of Particulate Matters for Single-Cylinder Diesel Engine[J]. Vehicle Engine, 2020
, 0(5)
: 55
-60
.
DOI: 10.3969/j.issn.1001-2222.2020.05.009
