液滴自由下落与液面冲击过程的三维数值

模拟#

5

10

摘要：液滴自由下落与液面冲击过程中涉及到液体的飞溅、融合与跃动等非常复杂的界面变

形。基于三维非稳态的 Navier-Stokes 方程，采用有限体积法、高分辨率 STACS 格式的 VOF

方法及连续表面张力模型(CSF)，建立了一个能精确描述自由面流动的数学模型。应用该

模型对剪切流场进行了三维模拟，检验其可行性。并进一步对液滴自由下落与液面冲击过程

进行了数值模拟。数值结果表明，模型能成功的捕捉到三维液滴撞击、变形、反弹、形成空

腔和水柱跃起的水体运动过程和水动力作用过程，描述气液界面的精度较高，可应用于三维

气液复杂界面流的问题研究。

关键词：液滴；气液两相流；VOF 方法；高分辨率

中图分类号：P731.22; TV139

15

Three-dimensional Numerical Simulation of Free-fall Drop

Impact onto the surface of a Liquid Pool

JIANG Changbo, DENG Bin, LONG Yuannan, CHEN Jie

(School of Hydraulic Engineering, Changsha University of Science & Technology,

20

25

30

35

40

ChangSha 410004)

Abstract: Free-fall drop impact onto the surface of a liquid pool is a good example for interface

modeling methods since it involves complicated flow deformations such as splashing, coalescence

and bouncing. Besed on three-dimensional unsteady Navier-Stokes equations,The finite volume

method was used to discretize the governing equations. A numerical model with free-surface flow

of high precision was established by using a High-resolution scheme of VOF method (STACS)

and Continuum Surface Force(CSF) model. The validity of the simulation following this model

was examined through shearing flow phenomena. It was used to detailedly simulate the whole

process of the droplet free falling and its impact onto the surface of a liquid pool then. The

simulated results show that this model can predict the hydrodynamics and interaction

characteristics of 3D drop impacting, deformation, bouncing and so on. The current method gives

remarkably fine features of the interface, and it can be applied to investigate the three-dimension

gas-liquid two-phase flow problems with complicated free-surface flow.

Keywords: Drop; Two-pahse Flow; VOF method; High-resolution

0 引言

液滴冲击液面的物理现象广泛存在于自然界和工程应用中，如雨水对地面的冲击与侵

蚀、喷墨打印、内燃机燃油的喷射、喷雾或喷淋冷却等；另外水利工程中的掺气、泄洪消能

和雾化问题，核安全工程中对高温熔融液滴冲击气液界面时的破碎问题都可以窥到它熟悉的

影像。液滴冲击液面的现象是这些物理过程的重要组成部分，是这些工程领域基本的研究课

题之一。液滴冲击有限空间内具有自由液面的水体时，两种不同形式的自由表面发生碰撞，

液滴和水体迅速发生变形