甲醇/二甲醚双燃料复合燃烧过程的多维数值模拟  

Multi-Dimensional Numerical Simulation on Compound Combustion Process with Methanol/Dimethyl Ether Dual-Fuel

作　　者：陈征[1] 尧命发[1] 郑尊清[1] 张全长[1] 

机构地区：[1]天津大学内燃机燃烧学国家重点实验室,天津300072

出　　处：《天津大学学报》2009年第7期574-580,共7页Journal of Tianjin University(Science and Technology)

基　　金：国家自然科学基金资助项目(50376046);国家自然科学重点基金资助项目(50636040)

摘　　要：采用计算流体动力学耦合简化动力学模型研究了甲醇喷射时刻对甲醇/二甲醚(DME)双燃料复合燃烧过程的影响机理.结果表明,甲醇在上止点前26.°CA喷射,对DME低温反应几乎没有影响,但对DME高温反应有明显的促进作用,DME和甲醇的高温反应几乎同时发生;甲醇在上止点前26.°CA喷射,高温燃烧区集中在燃烧室内部,导致大量的NO生成;而甲醇在上止点前6°CA喷射,高温燃烧区分散在压缩余隙和燃烧室内壁附近,NO生成量明显降低,但燃烧持续期延长.甲醇喷射时刻的合理选择是复合燃烧取得最佳综合性能的关键.The effect of methanol injection timing on the dual-fuel compound combustion with methanol/dimethyl ether （DME） was numerically investigated by adopting computational fluid dynamics（CFD） coupled with simplified dynamics model. The simulation results show that as methanol is injected at -26°CA ATDC ,the low temperature reaction of DME is hardly affected,but the high temperature reaction of DME is promoted clearly. The high temperature reaction of DME and that of methanol appear almost simultaneously for - 26 ° CA ATDC injection timing. When methanol is injected at -26 °CA ATDC ,the high temperature combustion region is concentrated within the combustion chamber so that a great deal of NO is formed. While methanol is injected at - 6 ° CA ATDC ,the high temperature combustion region is distributed in compression clearance and near combustion chamber wall so that the formation of NO is markedly decreased and combustion duration is prolonged. As a result,the proper methanol injection timing is the key to achieve optimal integrated performance of the dualfuel compound combustion with methanol/DME.

关 键 词：数值模拟 甲醇 二甲醚 双燃料 复合燃烧 喷射时刻 

分 类 号：TK421[动力工程及工程热物理—动力机械及工程]