Under the exhaust gas recycling (EGR) and lean-burn strategy, the effects of two strategies and compound method on performance, combustion and emission characteristics were studied based on a high-power methanol engine with injection ignition in the inlet port. The test results show that lean-burn can have higher cylinder pressure peak, shorter combustion duration, lower fuel consumption and higher effective thermal efficiency at the same dilution rate. Lean-burn strategy is more significant to reduce HC and CO emissions, but the EGR strategy can more effectively reduce NOx emission. In terms of unburned methanol and formaldehyde emissions, the lean-burn strategy has the better effect. Compared with EGR alone, compound dilution can significantly improve the effective thermal efficiency of methanol engine, has little influence on HC emission, can reduce CO emission by 80.3% at the largest that is similar to the excessive air dilution and better than EGR, can suppress NOx emission with a maximum reduction of 97%, but has an equivalent effect on unburned methanol emission that is higher than the excessive air dilution. When the compound dilution with a high degree is applied, formaldehyde emission will slightly reduce.
MENG Yuhang
,
SUN Nannan
,
ZHANG Mingze
,
JIA Demin
,
ZHANG Haiyan
,
ZHU Jianjun
. Effects of EGR and Lean-Burn on Combustion and Emission Characteristics of Methanol Engine[J]. Vehicle Engine, 2023
, 0(6)
: 10
-18
.
DOI: 1001-2222.2023.06.00
