摘要
为研究物性参数差异对苄基叠氮复合柴油液滴蒸发特性的影响,选择正十六烷作为柴油的替代物,在不考虑液相化学反应的前提下构建了苄基叠氮-正十六烷多组分液滴蒸发模型.然后利用该模型分析了液滴的蒸发过程,研究了苄基叠氮质量分数和环境温度对液滴蒸发过程的影响.结果表明,苄基叠氮-正十六烷液滴蒸发可分为瞬态加热阶段、混合蒸发阶段和平衡蒸发阶段.苄基叠氮由于其相对正十六烷较高的饱和蒸气压、较小的定压比热容以及较大的蒸气相扩散系数,因而具有较快的蒸发特性.随着苄基叠氮质量分数的增加,液滴蒸发速率不断提高;随着环境温度的升高,液滴升温速率不断增大,平衡蒸发温度不断升高,液滴蒸发速率不断增大,但是这一变化趋势并不与温度呈线性关系.
To understand the effects of different physical properties on vaporization characteristics of diesel-benzyl azide blend droplet,the hexadecane was used as a representative for diesel and a multicomponent vaporization model for a single hexadecane-benzyl azide blend droplet in the absence of liquid phase reaction was built. The vaporization characteristics and the effects of ambient temperature and benzyl azide mass fraction were analyzed. Results show that the vaporization history of hexadecane-benzyl azide droplet can be divided into three phases:the transient heating phase,the mixing vaporization phase,and the equilibrium vaporization phase. Benzyl azide vaporizes much faster because of its larger saturated pressure,smaller specific heat capacity under the constant pressure,and larger vapor/nitrogen binary diffusivity. With increasing benzyl azide mass fraction,the vaporization rate is increased. And with increasing ambient temperature,the droplet temperature increasing rate,equilibrium vaporization temperature and vaporization rate are increased nonlinearly.
出处
《内燃机学报》
EI
CAS
CSCD
北大核心
2014年第4期334-339,共6页
Transactions of Csice
基金
国家自然科学基金资助项目(51306021)
关键词
柴油
苄基叠氮
多组分
液滴蒸发模型
diesel
benzyl azide
multi-component
droplet vaporization model
