燃油喷射雾化机理的探讨

Research on Fuel Spray Mechanism

本文从空气动力干扰假说出发，通过分析油－气交界面上不稳定波波幅增长和破碎过程，定性和定量地探讨了索特平均直径及滴径分布。本文认为，燃油雾化过程可分为两阶段：一次雾化和二次雾化。一次雾化只发生在油－气交界面上，主要是喷注和空气之间的气动干扰作用，由射流表面产生不稳定波波幅增长和破碎所引起的；而二次雾化则发生在油气渗混区，由一次雾化后产生的油滴在空气中进一步破碎和相互聚合来决定。算例表明，燃油二次雾化假设及其对索特平均直径ＳＭＤ和滴径分布所作的定量分析是一次成功的尝试。

Based on the hypothesis of aerodynamic disturbance and by means of analyzing the amplitude increment and breakup process of instable wave on the oil-air interface, this paper has qualitatively and quantitatively studied SMD and droplets distribution. The present research suggests that the spray process can be divided into two stages: primary spray and secondary spray. The primary spray only takes place on the oil-air interface and is mainly caused by the amplitude increment and breakup due to the aerodynamic disturbance between spray and air; the secondary spray takes place in the oil-air mixing domains, it is under the control of the further breakup and coalescence of the droplets formed after the primary spray. Calculation examples show that the two-stage spray hypothesis of fuel and the quantitative analysis on the SMD and droplets distribution is asuccessful try.