Mechanism Analysis for Effect of Methanol on Diesel Ignition
LI Ruina1,WANG Zhong1,QU Lei2,LIU Shuai1
Author information+
(1.School of Automotive and Traffic Engineering,Jiangsu University,Zhenjiang 212013,China;2.School of Automotive and Traffic Engineering, Nantong Vocational University, Nantong 226007,China)
Show less
History+
Published
2019-02-25
Issue Date
2019-03-11
Abstract
The combustion process model of 4B26 diesel engine was established by AVL Fire software, the chemical reaction mechanism of methanol/nheptane was adopted, the changing law of incylinder temperature, fuel concentration and intermediate products were studied during the ignition process of methanol/diesel fuel on a diesel engine, and the ignition delay period based on the heat release rate, the intermediate product and the temperature was calculated. The results indicate that CH2O, H2O2 and OH show the most significant change among the intermediate products related to methanol decomposition before the ignition of methanol/nheptane and the intermediate product concentration shows the trend of double peaks. In the range between －7° and －5°, the dehydrogenation reaction of nheptane has been observed obviously compared with methanol. In the main reactions related to nheptane decomposition at low temperature, the CH4, C2H4 and C3H6 elementary reactions were more likely to occur. According to the instantaneous exothermic rate, the dehydrogenation of nheptane, OH concentration and the change of incylinder temperature field, the corresponding ignition timing of methanol/nheptane is －7.2°, －7°~－5°, －2.4° and －5.8°respectively. The determined ignition timing from OH concentration is relatively late in all kinds of judgments.
LI Ruina,WANG Zhong,QU Lei,LIU Shuai.
Mechanism Analysis for Effect of Methanol on Diesel Ignition[J]. Vehicle Engine. 2019, 0(1): 27-33 https://doi.org/10.3969/j.issn.1001-2222.2019.01.005
