液滴二次雾化破碎模式数值模拟

在许多现代工程领域中，二次雾化对于增强液体雾化以及提高混合率都起到了关键的作用．基于SIMPLE方法对这个问题进行了数值模拟，VOF方法与Level-Set方法耦合捕捉界面，自适应网格的运用平衡了对提高计算精度以及降低计算成本两方面的要求．在Oh数较低(Oh < 0.1)的情况下，通过数值模拟得到了四种典型的液滴分裂模式，并且对其中相对复杂的第二第三种分裂模式进行了详细的分析与比较．得出了该模式形成的条件与相关特性．最后，将以上结果与前人的实验结果作了对比，在大多数重要特征方面，两者有非常好的一致性．

Numerical Simulation of Droplet Breakup Regimes in Secondary Atomization

The secondary atomization plays a key role in increasing both evaporation and mixing rates in a variety of engineering applications. The phenomenon was studied by numerical simulation based on SIMPLE scheme. The VOF method, coupled with the Level-Set method, was used to capture the boundary; the adaptive mesh strategy was taken to balance the demands for raising accuracy of calculation and for reducing computational expenditures. In the case of low Oh number, when Oh < 0.1, four typical regimes of droplet breakup are observed in the simulation; and the comparatively more complicated the second and the third modes had undergone detailed analysis and comparison. The condition for the occurance of these modes and the pertinent features were obtained. Finally, comparison between these results and those of past experiments were made; in most part of significant aspects the two have very good agreement.