Study on the Regulation of Electromagnetic Stirring of Liquid Metal.

液态金属电磁搅拌调控研究。

基本信息

批准号：
01850147
负责人：
KIKUCHI Atsushi
金额：
$ 6.46万
依托单位：
Tohoku University
依托单位国家：
日本
项目类别：
Grant-in-Aid for Developmental Scientific Research (B).
财政年份：
1989
资助国家：
日本
起止时间：
1989 至 1990
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-01850147/
关键词：
High Frequency Induction Furnace Electromagnetic Stirring Flow of Liquid Iron Regulation of Stirring Magnetohydrodynamics Refining Reactions Kinetic Study Mass Transfer 誘導攪拌誘導撹拌撹拌制御

项目摘要

The high frequency induction furnace is often used for fundamental studies concerning the molten metals, but it is impossible to change the stirring intensity widely under a constant temperature. This limitation prevents the advancement of the metallurgical kinetic studies. The present study proposes two methods to provide a means of regulating the flow intensity widely based on a conventional induction furnace. The characteristics of the flow regulation have been checked experimentally and theoretically.1. Flow Regulation by Electrically Conductive Rings(1) Method : A ring made from graphite or molybdenum is located between a crucible and a heating coil to absorb a part of the magnetic fluxes which penetrate in a liquid iron and generate the stirring forces. The fraction of absorption can be regulated by the apparent resistivity which is changed by the shape of the ring.(2) Experiments : The measurements of the magnetic flux densities in the furnace and the experiment on dissolution o … More f a graphite rod in a liquid iron have been made. The distributions of the magnetic flux densities and local mass transfer coefficients have been found to change extremely with the change in the resistivity of the ring. From these results, it is concluded that the flow regulation is enabled by using the ring. However it seems difficult to connect the ring to a variable resistance for more convenient operation.2. Flow Regulation by a Secondary Coil(1) Method : A water cooled copper coil (secondary coil) which is connected to an external coil, variable turn numbers, is located out of a crucible near the free surface of liquid iron. The magnetic fluxes near the secondary coil can be changed by changing the turn numbers of the external coil.(2) Experiments : The same experiments as the above ones have been made and the flow regulation by changing the turn numbers of the external coil connected to the secondary coil has been realized experimentally.3. Theoretical StudyThe mutual inductance model is applied to the electromagnetic field in the furnace. The computed results on the magnetic flux densities agree well with the observed ones. The fluid flow and mass transfer in liquid iron have been analyzed numerically on the basis of the Navier-Stokes equation and the conservation equation of carbon in liquid iron. The computed results have supported the capability of the secondary coil methods. Less

高频感应炉经常用于有关熔融金属的基础研究，但不可能在恒定温度下广泛改变搅拌强度，这一限制阻碍了冶金动力学研究的进展。目前的研究提出了两种方法。一种在传统感应炉的基础上广泛调节流量强度的方法。流量调节的特性已通过实验和理论进行了验证。1．导电环流量调节方法：由石墨或石墨制成的环。钼位于坩埚和加热线圈之间，吸收部分渗透到铁液中并产生搅拌力的磁通量，吸收部分可以通过环的形状改变的视电阻率来调节。 (2)实验：进行了炉内磁通密度的测量和石墨棒在铁水中溶解的实验，得到了磁通密度和局部传质系数的分布。已经发现随着环的电阻率的变化而发生极大的变化，从这些结果可以得出结论，通过使用环来实现流量调节，但是将环连接到可变电阻以更方便地操作似乎很困难。 .2. 通过次级线圈调节流量(1) 方法：连接到可变匝数的外部线圈的水冷铜线圈（次级线圈）位于靠近液态铁自由表面的坩埚外。次级线圈附近的磁通量可以通过以下方式改变(2)实验：进行了与上述相同的实验，实验上实现了通过改变与次级线圈相连的外部线圈的匝数来调节流量。3．研究将互感模型应用于炉内电磁场，计算结果与观测结果吻合良好，并基于纳维-斯托克斯对铁液中的流体流动和传质进行了数值分析。方程和铁液中碳守恒方程的计算结果支持了次级线圈法的能力。