双燃料发动机低温燃烧排放性能仿真

为缓解船用发动机NOx排放过高问题，提出柴油掺烧丁醇并结合EGR（exhaust gas recirculation）技术的试验方案。在4190ZLC-2型柴油机台架基础上，利用AVL_FIRE软件建立柴油-丁醇CFD模型。设置丁醇掺混比0%、10%、20%、30% 4组变量，EGR利用率0%、7.5%、10.0%、12.5%、15.0%、17.5% 6组变量，对发动机NO、碳烟（Soot）和CO生成及排放质量分数进行分析。结果表明:掺烧丁醇并结合EGR能够实现发动机的低温燃烧，减少CO和碳烟的生成，且显著降低NO排放。当丁醇掺混比为B20、EGR利用率12.5%组合时，NO排放比原机降低58.97%，Soot生成质量峰值比原机降低37.5%，CO排放比原机降低23.53%。研究结果可为船用柴油机采用柴油/丁醇/EGR低温燃烧提供一定的指导依据。

Simulation of Low-Temperature Combustion Emission Performance of Dual-Fuel Engine

In order to alleviate the problem of excessive NOx emission from Marine engine，a test scheme of diesel mixed with butanol combined with EGR technology was put forward.On the basis of 4190ZLC -2 diesel engine bench，the CFD model of diesel butanol was established by AVL_FIRE software.Four groups of variables of butanol mixing ratio 0% ，10%，20% and 30% were set，and EGR utilization ratio 0%，7.5%，10.0%，12.5%，15.0% and 17.5% were set.The generation of NO ，Soot and CO and emission mass fraction of engine were analyzed.The results show that the combination of butanol and EGR can achieve lower temperature combustion ，reduce the generation of CO and Soot，and significantly reduce NO emission.When the butanol mixing ratio is B20 and EGR utilization ratio is 12.5% ，the NO emission，peak quality of Soot and CO emission are 58.97%，37.5% and 23.53% lower than the original.The research results can provide some guidance for lower temperature combustion of diesel/butanol /EGR for Marine diesel engines.