动量比对两股互击式喷嘴雾化特征的影响

Effect of momentum ratio on atomization characteristics of unlike-doublet impinging jets injector

基于CLSVOF(coupled level-set and volume of fluid)方法对两股互击式喷嘴雾化过程进行了数值模拟,仿真结果与实验结果进行对比,并详细考察了动量比对液膜特性的影响.结果表明:1CLSVOF方法能对射流撞击形成的液膜形态进行有效捕捉,计算获得的液膜形态与实验结果一致.2两股不同孔径的射流在撞击点撞击过程中,由于大孔径一侧的部分射流未参与撞击,而中心位置的液体在撞击之后速度迅速下降,周围的液体则保持撞击前的速度,使得射流撞击之后形成弧形状液膜.3在不同动量比条件下,射流撞击后轴线位置的合成角主要取决于参与撞击射流的动量比,数值计算结果与理论计算结果吻合较好,误差均小于10%.

Numerical simulation was carried out on the atomization process of unlikedoublet impinging jets injector based on the CLSVOF （coupled level-set and volume of fluid） method. The simulation results were compared with the experiment results, and the effect of momentum ratios on liquid sheet characteristics was investigated in detail. The results show that： （1） The CLSVOF method can efficiently capture the liquid sheet characteristics formed by jet impact. The calculated liquid sheet agrees well with the experiment result. （2） In the impinging process of jets, part of the jet flow of large diameter nozzle is not involved in the impact, while the velocity of liquid in the central position drops rapidly after impact, and at the same time, the surrounding liquid maintains the velocity before impact, which results in the formation of cured liquid sheet. （3） Under the conditions of different momentum ratios, the resultant angle in the axis position after impact mainly depends on the momentum ratio of impinging jets. The simulation results are in good agreement with the theoretical calculation results, with the errors less than 10%.