权益分类	功能权益	普通用户	{{item.name}}会员
{{category.name}}	{{benefitItem.name}}

INTERACTION FORCE BETWEEN PARTICLES SUSPENDED IN LIQUID METAL IN THE CASE OF TURBULENT AGGLOMERATION

湍流团聚情况下液态金属中悬浮颗粒之间的相互作用力

基本信息

批准号：
10450276
负责人：
TANIGUCHI Shoji
金额：
$ 1.73万
依托单位：
TOHOKU UNIVERSITY
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (B)
财政年份：
1998
资助国家：
日本
起止时间：
1998 至 1999
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-10450276/
关键词：
inclusion agglomeration of inclusion turbulent flow Hamaker constant van der Waals force clean steel vander Waals力 van der Waals力

项目摘要

The mechanism of the agglomeration of inclusion particles in liquid metal is not made clear enough for achieving the highly clean metal products. In the previous studies on the agglomeration of inclusion particles, the hydrodynamic effect on the collision between particles is taken into account, however, the role of inter-particle force such as van der Waals force has been disregarded, which is important for the process of particle agglomeration. In the present study, the following investigations have been made to make clear the role of inter-particle force in the agglomeration of inclusion particles in turbulent flow of liquid metal.1. Experiment on the agglomeration of PSL particles in aqueous solution : Agglomeration curves of polystyrene-latex particles (PSL) which had a uniform size and spherical shape were measured in an agitated NaCl-aqueous solution. By applying the calculated curve obtained by the agglomeration theory composed of hydrodynamics and inter-particle force on the m … More easured agglomeration curves, the Hamaker constant, the characteristic of the van der Waals force, was determined. This value agreed well with the literature value of PSL. A mathematical model (grouping model) was newly developed to estimate the size distribution of agglomerated particles by a simple procedure.2. Experiment on the agglomeration of SiC particles in aqueous solution : SiC particle was used as the model of inclusion particle and agglomeration curves were measured in an agitated NaCi solution. It was found that the breakup of agglomerated particles took place in the later stage of agglomeration. The grouping model was modified to include the breakup phenomenon and adopted measured agglomeration curves, and as a result, the Hamaker constant of SiC was determined, which agreed with the literature value.3. Experiment on the agglomeration of SiC particles in molten aluminum : An ultrasonic homogenizer was constructed and adopted successfully to the dispersion of SiC particles in molten aluminum. Agglomeration of SiC particles in the molten aluminum under turbulent agitation was observed in some preliminary experiments. However, quantitative analysis of agglomeration was not carried out because of the problem of the reproducibility. The behavior of SiC particles in molten aluminum was investigated under the electromagnetic agitation and the separation of particles by the electromagnetic force was clearly observed. In the experiment, particles with 13μm and 23μm in average diameter were used, and in the case of larger particle, separation was found to proceed before agglomeration. On the contrary, the smaller particle was found to agglomerate first and then be separated.In conclusion, the importance of inter-particle force in the inclusion agglomeration was made clear and the measure for understanding the mechanism of inclusion particles in liquid metal was given in this study. Less

夹杂物颗粒在液态金属中团聚的机理还不够清楚，无法获得高纯度的金属制品。在以往关于包裹体颗粒团聚的研究中，考虑了流体力学对颗粒间碰撞的影响，而忽略了范德华力等颗粒间作用力的作用，而范德华力是颗粒团聚过程中的重要因素。在本研究中，为了弄清颗粒间作用力在液态金属湍流中夹杂物颗粒聚集过程中的作用，进行了以下研究。聚苯硫醚粒子在水溶液中团聚的实验：测定了聚苯乙烯-乳胶粒子(PSL)在搅拌的氯化钠水溶液中的团聚曲线。应用由流体力学和粒间作用力组成的团聚理论计算的m-…曲线测量了更多的团聚曲线，确定了表征范德华力的Hamaker常数。这一价值与PSL的文献价值很好地吻合。建立了一种新的数学模型(分组模型)，通过一个简单的步骤来估计团聚颗粒的尺寸分布。碳化硅颗粒在水溶液中的团聚实验：以碳化硅颗粒作为包裹体颗粒的模型，测定了其在NaCI溶液中的团聚曲线。结果表明，团聚颗粒的破碎发生在团聚后期。对分组模型进行了修正，加入了碎裂现象，并采用了测量的团聚曲线，由此确定了碳化硅的Hamaker常数，与文献值吻合。碳化硅颗粒在铝液中团聚的实验研究：研制了一台超声均质机，并成功地应用于碳化硅颗粒在铝液中的分散。在一些初步实验中，观察到了在湍流搅拌下碳化硅颗粒在铝液中的团聚现象。然而，由于重现性问题，没有对团聚进行定量分析。研究了电磁搅拌作用下碳化硅颗粒在铝液中的行为，观察到了颗粒在电磁力作用下的分离。在实验中，使用了平均直径为13μm和23μm的颗粒，对于较大的颗粒，在团聚之前进行了分离。结果表明，颗粒间相互作用力在夹杂物团聚过程中的重要性，为理解夹杂物颗粒在液态金属中的形成机理提供了手段。较少