Hypothesis

When multiple drops impact on a thin liquid film, the interaction dynamic between two impinging drops is prominent. High-speed (>50 m/s) oblique impacts of drops on a liquid film result in asymmetrical splashing patterns and further complicate the phenomenon. To understand the interaction between injected crowns from splashing, numerical simulations are very useful to study the flow behaviors.

Simulations

Three-dimensional simulations are performed to investigate the impact of two adjacent drops on a thin liquid layer using a multiphase flow solver. The solver solves Navier-Stokes equations on Cartesian grids and uses the moment-of-fluid method for interface reconstruction. The numerical code is first validated with three experimental studies and good agreements are obtained. Simulations of oblique impacts of two adjacent drops are then conducted for low-speed and high-speed impacts.

Findings

The numerical results show that strong interaction occurs when the crowns formed by two adjacent drops interfere with each other. For low-speed impact, drops deposit on to the liquid film with short and thick crater rims formed and the interaction region is a superposition of the crater edges. For high-speed impact, crowns break up to form splashing and the interaction behavior becomes complicated.

中文翻译：

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液滴对液体薄膜倾斜影响的数值研究

假设

当多个液滴撞击薄膜液体时，两个撞击液滴之间的相互作用非常明显。液滴在液膜上的高速（> 50 m / s）倾斜冲击会导致喷溅图案不对称，并使现象更加复杂。为了了解飞溅引起的注入冠之间的相互作用，数值模拟对于研究流动行为非常有用。

模拟

使用多相流求解器进行了三维模拟，以研究两个相邻液滴对薄液体层的影响。求解器在笛卡尔网格上求解Navier-Stokes方程，并使用流体矩方法进行界面重建。首先通过三项实验研究验证了数字代码，并获得了良好的协议。然后针对低速和高速撞击进行两个相邻液滴的倾斜撞击的模拟。

发现

数值结果表明，当两个相邻液滴形成的冠相互干扰时，会发生强相互作用。对于低速冲击，液滴沉积在液膜上，形成短而厚的火山口边缘，相互作用区域是火山口边缘的叠加。对于高速冲击，冠部破裂而形成飞溅，并且相互作用行为变得复杂。