Based on a single-cylinder two-stroke optical engine, the visualization study of fuel-air mixing and combustion process of n-dodecane was carried out according to different injection strategies under the same thermodynamic conditions. High-speed schlieren imaging was used to observe the transient changes of spray geometry and measure the flame lift length. The heat release rate was obtained through the cylinder pressure curve to study the combustion process. The difference between the two-stage fuel injection strategies lied in the different fuel injection intervals and initial fuel injection volumes. The results show that the fuel injection interval and the initial fuel injection volume have no significant effect on the second ignition delay period and flame lift length, but the flame lift length is more sensitive to the fuel injection interval than the ignition delay period. The combustion efficiency of the entire injection process will not change with the change of fuel injection interval or the duration of first fuel injection, but the combustion efficiency of the second injection is always higher than that of the first fuel injection.
ZHANG Shiqian
,
BI Qing
. Combustion Characteristic of Fuel Spray Based on SplitInjection Strategy[J]. Vehicle Engine, 2020
, 0(6)
: 53
-59
.
DOI: 10.3969/j.issn.1001 2222.2020.06.009
