单进口压力漩流喷嘴雾化半角仿真计算研究

Study of Semi-spray Angle Calculation in Single Inlet Pressure-swirl Atomizer

在分析单进口喷嘴与多进口喷嘴内部流场特点的基础上,针对航空发动机单进口喷嘴流场空间上不对称,时间上不稳定的特点,采用空间各点平均和多时间点平均的方法改进雾化半角的计算方法,给出了一种计算单进口小型压力漩流喷嘴雾化半角的数学模型。在判断喷嘴内部流场状态的基础上,采用CFD流体仿真软件计算喷嘴内部流动参数,得到喷嘴出口速度分布,结合改进的雾化半角计算方法,总结喷嘴结构尺寸对雾化半角的影响规律。计算结果表明:雾化半角随出口长度、漩流室长度的增加而减小,随出口外倒角的增加而增加,但是各参数对雾化半角的影响存在不同的特点:当出口长度较小时增加出口长度雾化半角迅速减小,而当出口长度较大时这种减小趋势较缓慢;漩流室长度对雾化半角的影响基本呈线性;出口倒角在10°～20°之间时对雾化半角的影响较大。

Basing on the analysis of the characteristic of internal flow in single inlet pressure-swirl atomizer and multi-inlet pressure-swirl atomizer, the calculation of semi-angle is improved against the unsymmetrical characteristic of above atomizer. Through calculating of the velocity profile at outlet, the mathematical model is proposed for single inlet pressure-swirl atomizer. CFD com- mercial software is adopted to calculate the semi-spray angle as changing parameters of atomizer. The law of semi-spray angle is gotten in different structures as follows ： The semi-spray angle decreases as increasing the length of outlet and swirl chamber; The semi-spray angle is monotone increasing as the increasing of outward cone angle.