燃料特性对乙醇-正丁醇-十四烷燃油雾化特性的影响分析  

Influence of Fuel Properties on Atomization of Ethanol-n-butyl-n-tetradecane Blend Fuel

作　　者：胡鹏[1] 王伟[1] 琚雪明[1] 

机构地区：[1]奇瑞汽车股份有限公司动力总成技术中心,安徽芜湖241009

出　　处：《汽车工程学报》2016年第1期43-49,共7页Chinese Journal of Automotive Engineering

基　　金：江苏省普通高校研究生科研创新计划(CXZZ12_0675)

摘　　要：为探讨燃料特性促进柴油机缸内乙醇柴油雾化过程的影响机理,采用单组份十四烷代替实际多组分柴油,利用经典KH模型和TAB模型数值分析燃料特性对乙醇-正丁醇-十四烷混合燃料初次和二次雾化的影响规律。结果表明,十四烷中掺混乙醇和正丁醇后初次雾化团块液核半径和破碎时间均降低,有助于燃油在喷油器油嘴附近撕裂,促进柴油机近喷嘴区燃油初次雾化;在相同的条件下,乙醇柴油理化性质对二次雾化的影响很小;液滴半径越小,破碎后Sauter平均半径和破碎时间对半径增量敏感性越强,越容易发生二次雾化;良好初次雾化和液滴蒸发特性促进液滴二次雾化和液滴蒸发。In order to investigate the effect of fuel properties on the atomization of ethanol-diesel blended, the primary atomization of liquid jet and secondary atomization of droplet were calculated by KelvinHelmholtz instability（KH） model and taylor analogy breakup（TAB） Model, respectively. The diesel was replaced by n-tetradecane in the model. The results indicate that the liquid core radius and breaking time of the primary atomization of liquid jet of ethanol-diesel are reduced. Adding ethanol and n-butyl alcohol to n-tetradecane is beneficial to fuel spray atomization near the nozzle exit in diesel engine. Under the same conditions, fuel properties have little effect on secondary atomization of droplet. For smaller radius of droplet, the sensitivity of the droplet radius and breaking time of secondary atomization to droplet radius is stronger, and it is easier to induce secondary atomization of droplet. Good primary atomization and droplet evaporation characteristic can promote the secondary atomization of droplets and droplet evaporation.

关 键 词：内燃机 乙醇柴油 燃料特性 初次雾化 二次雾化 

分 类 号：TK402[动力工程及工程热物理—动力机械及工程]