Shock wave formation in droplet impact on a rigid surface: lateral liquid motion and multiple wave structure in the contact line region
Shock wave formation in droplet impact on a rigid surface: lateral liquid motion and multiple wave structure in the contact line region
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DOI：
10.1017/s0022112003005093
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发表时间：
2003-09-10
影响因子：
3.7
通讯作者：
Monkewitz, P
中科院分区：
文献类型：
--
作者：
Haller, KK;Poulikakos, D;Monkewitz, P
高速液滴撞击刚性壁面的早期阶段是通过在接触区周围产生冲击波而产生的可压缩性效应。最初，压缩液体的面积被假设为受激波包络的边界，激波包络既横向又向上传播到液体的主体中。本文建立了压缩区域内液体横向运动的解析模型，并与无粘(欧拉)流动方程的轴对称数值解进行了比较。结果表明，通常采用的假设，即在接触线上附加单个冲击波将压缩区域与液体散体分开，这一假设是错误的，并导致了异常。这种反常现象出现在冲击波离开接触线之前，开始横向液体喷射。为了消除这种异常，本文提出的分析模型提出了在喷流喷发之前，接触线区由单波结构向多波结构的转变。数值结果也支持这种更为复杂的多波结构的出现。
The early phase of high-speed liquid droplet impact on a rigid wall is characterized by compressibility effects through the creation of a shock wave attached to the contact area periphery. Initially, the area of compressed liquid is assumed to be bounded by the shock envelope, which propagates both laterally and upwardly into the bulk of the liquid. In this paper, an analytical model accounting for the lateral liquid motion in the compressed area is developed and compared to the axisymmetric numerical solution of the inviscid (Euler) flow equations. It is shown that the often employed assumption that the compressed area is separated from the liquid bulk by a single shock wave attached to the contact line breaks down and results in an anomaly. This anomaly emerges prior to the time when the shock wave departs from the contact line, initiating lateral liquid jetting. In order to remove this anomaly, the analytical model presented in this paper proposes the transition from a single to a multiple wave structure in the contact line region, prior to jetting eruption. The occurrence of this more complex multiple wave structure is also supported by the numerical results.