组喷孔喷雾雾化特性研究

基于修正的喷雾模型,对组喷孔雾化特性进行了数值研究.计算结果表明平行组喷孔中喷孔直径减小所带来的微孔效应以及喷雾重叠区域的射流交互作用,使得其喷雾同单喷孔类似,均具有良好的轴对称性.平行组喷孔喷雾贯穿度略小于等截面单喷孔,而明显大于等直径单喷孔.随着喷孔间距以及夹角的增加,喷雾射流交互作用下降,组喷孔喷雾贯穿度下降,喷雾SMR(索特半径)下降,同时也逐渐失去轴对称性.相对于收缩型组喷孔,扩张型组喷孔失去轴对称性更快,喷雾贯穿度下降更多.

Spray Atomization Characteristics of Group-hole Nozzle

The atomization characteristics of group-hole nozzle were numerically investigated with the revised spray model. The results show that due to the compromise effect of micro-orifice from the reduction of nozzle diameter and jet interaction from the overlapping part of spray, the spray of parallel group-hole nozzle is similar to that of the single nozzle, both of which have good axial symmetry. However, the spray penetration of the parallel group-hole nozzle is slightly lower than that of single nozzle with the equivalent hole area, and is significantly larger than that of single nozzle with the same hole diameter. With the increase of the hole spacing and inclined angle, the jet interaction decreases, which results in the reduction of the spray penetration and SMR of the group-hole nozzle. Meanwhile, the spray axial symmetry of group-hole nozzle is finally lost. Compared to the converging group-hole nozzle, it is faster for the diverging group-hole nozzle to lose the spray axial symmetry and decrease the spray penetration.