摘要
采用水模型实验和高速摄像技术模拟了钢液中气泡与液滴碰撞聚合的现象和机理。根据韦伯数We和碰撞参数B的关系,气泡和液滴的碰撞结果分为聚合、反弹和拉伸分离3种。聚合分为靠近碰撞、形成液膜、形成稳定接触面、滑移、稳定上浮等过程;反弹分为靠近碰撞、形成液膜、滑移分离等过程;拉伸分离分为靠近碰撞、形成液膜、形成接触面和共同体、形成颈部、断裂等过程。当We很小时,气泡和液滴会发生聚合。随着We的增大,B适中时,两者聚合;B过小,两者反弹;B过大,两者拉伸分离。在实验的We范围内,3种结果中聚合情况最多。由此,根据相似性可以解释在钢液中少见液滴夹杂物的原因。
Phenomenon and mechanism of collision and coalescence between bubble and droplet were simulated by high speed photograph technology in water model experiment. According to the relationship between Weber number （We） and impact parameter （B）, the collision results of bubble and droplet can be divided into 3 types which are coalescence, bouncing and stretching separation. The coalescence process can be decomposed into 5 sub- processes： proximity and collision, the formation of liquid film, the formation of a stable contact surface, sliding, stable floating process; the bouncing process can be decomposed into 3 sub-processes： proximity and collision, the formation of liquid film, sliding and debonding; the stretching separation process can be decomposed into 5 subprocesses： proximity and collision, the formation of liquid film, the formation of contact surface and community, the formation of neck, breaking. When Weber number is very small, bubble and droplet will aggregate. With the increase of We, when B is moderate, bubble and droplet can be coalescent; when B is small, and they can bounces when B is high, they can separate by stretch. In the range of We of the experiment, the most popular phenomenon in the three kinds of results is the polymerization. Thus the reason why the droplet inclusions are rare in molten steel can be explained by the similarity theory.
出处
《钢铁研究学报》
CAS
CSCD
北大核心
2017年第9期717-723,共7页
Journal of Iron and Steel Research
基金
国家自然科学基金资助项目(51374081)
关键词
气泡
液滴
夹杂物
碰撞
聚合
bubble
droplet
inclusion
collision
coalescence
