LBM方法数值模拟飞溅流动的影响因素研究

文章采用格子Boltzmann单相自由面模型模拟飞溅流动问题,以楔形体入水问题为模拟对象,研究了网格精细度、计算域、水动力相似参数对飞溅效果的影响。研究表明,亿量级网格下入水飞溅射流及飞溅端部的细小液滴结构十分清晰,模拟结果明显优于百万量级、千万量级网格;计算域超过模型尺度3倍后飞溅效果不受影响;以自由液面面积S的增长率η为比较参数,当Re数、Fr数较小时对飞溅效果有明显影响,大于一定数值后,飞溅效果基本一致。

Influence factors to numerical simulation of splash flow based on LBM

The single-phase free surface Lattice Boltzmann Model (LBM) is used to simulate the splash flow. Wedge water-entry problem is simulated to study the splash characteristics influenced by grid refinement, computational domain and hydrodynamic similarity parameters. The results show that the flow structure of the splash jet is much finer with a grid of hundreds million size compared to the coarse ones. With the com-putational domain of more than three times of the size of wedge, it could get almost the same splash charac-teristics. Reynolds number and Froude number will significantly affect the splash structure when they are in small values;while they are large enough, the splash images will keep similar.