由两组线圈产生的高频行波磁场可用于驱动低电导率的液体，因此对其机理的研究具有重要意义。建立该驱动方式的数值模型，研究线圈电流大小、频率、相位差以及线圈间距对低电导率液体的流场与温度场的影响，从而获得最佳的电气参数配置以及线圈结构。模拟计算结果表明：流体的平均流速和平均温度与电流大小和频率均为线性关系。流体的平均流速随电流的相位差增加呈先增大后减小的规律，且在相位差为90°附近达到最大值。随着线圈间的距离变化，流场的分布形式从2个涡流转变为单个大环流。此外还采用粒子图像测速技术测量NaCl溶液在高频行波磁场驱动下的流场分布，验证该驱动方式的可行性和有效性。
郭胜荣
,
那贤昭
,
刘润聪
,
李勇
,
张香平
,
董海峰
,
戴晓天
,
巩秀芳
,
王晓东
. 高频行波磁场驱动低电导率液体流动的数值模拟[J]. 中国科学院大学学报, 2023
, 40(1)
: 21
-28
.
DOI: 10.7523/j.ucas.2021.0029
High frequency traveling magnetic field generated by two sets of coil can be applied as a new driving method for low conductivity liquid, therefore study on its mechanism is of great significance. In this paper, a numerical model is established to study the effects of current, frequency, phase difference， and coil distance on the flow field and temperature field of the low conductivity liquid being driven, so as to obtain the optimal electrical parameters configuration and coil structure for the driving task. The simulation results show that the average velocity and temperature of the fluid are linearly correlated with the magnitude and frequency of the current. The average velocity is maximized when the phase difference between the coils is near 90o. Depend on the coil distance, the flow field is either two vortices or a single large circulation. Particle image velocimetry (PIV) is also used to measure the flow field distribution of NaCl solution driven by high frequency traveling magnetic field, which verifies the feasibility and effectiveness of the driving method.
[1] 任忠鸣，雷作胜，李传军，等. 电磁冶金技术研究新进展[J]. 金属学报，2020，56(4)：583-600.DOI：10.11900/0412.1961.2019.00373.
[2] Li X，Wang X H，Bao Y P，et al. Effect of electromagnetic stirring on the solidification behavior of high-magnetic-induction grain-oriented silicon steel continuous casting slab[J]. The Journal of the Minerals, Metals & Materials Society, 2020, 72(10): 3628-3633.DOI：10.1007/S11837-020-04058-y.
[3] Liu H P，Wang X H，Si L Y，et al. Numerical simulation of 3D electromagnetic-thermal phenomena in an induction heated slab[J]. Journal of Iron and Steel Research International, 2020, 27(4): 420-432.DOI：10.1007/S42243-020-00362-8.
[4] Damoah L N W，Zhang L F. High-frequency electromagnetic purification of silicon[J]. Metallurgical and Materials Transactions B, 2015, 46(6): 2514-2528.DOI：10.1007/S11663-015-0447-2.
[5] Zhang L S，Zhang X F，Wang B，et al. Numerical analysis of the influences of operational parameters on the braking effect of EMBr in a CSP funnel-type mold[J]. Metallurgical and Materials Transactions B, 2014, 45(1): 295-306.DOI：10.1007/S11663-013-9948-z.
[6] 王进进，张杰，倪明玖. 均匀磁场中初始静止的液态金属在电流作用下三维运动的数值研究[J]. 中国科学院大学学报，2015，32(2)：166-171.DOI：10.7523/j.issn.2095-6134.2015.02.004.
[7] Iwata H，Yamada K，Fujita T，et al. Electromagnetic stirring of molten core in continuous casting of high carbon steel[J]. Transactions of the Iron and Steel Institute of Japan, 1976, 16(7): 374-381.DOI：10.2355/isijinternational1966.16.374.
[8] Khine Y Y，Walker J S. Thermoelectrically driven melt motion during floating zone crystal growth with an axial magnetic field[J]. Journal of Fluids Engineering, 1998, 120(4): 839-843.DOI：10.1115/1.2820748.
[9] Farahat R，Eissa M，Megahed G，et al. Effect of EAF slag temperature and composition on its electrical conductivity[J]. ISIJ International, 2019, 59(2): 216-220.DOI：10.2355/isijinternational.isijint-2018-507.
[10] 王璐璐，周勇军，鲍苏洋，等. 改进型INTER-MIG桨搅拌槽内流场的PIV实验[J]. 过程工程学报，2017，17(3)：447-452.DOI：10.12034/j.issn.1009-606X.216263.
[11] 谢开旺，刘明，刘静，等. 电磁泵驱动室温金属流体的数值模拟与试验研究[J]. 电子机械工程，2009，25(3)：1-5,23.DOI：10.19659/j.issn.1008-5300.2009.03.001.
[12] 任兵芝，朱苗勇，王宏丹，等. 大方坯连铸结晶器电磁搅拌三维电磁场与流场的数值模拟[J]. 金属学报，2008，44(4)：507-512.
[13] 赵菲. 圆坯连铸结晶器电磁搅拌磁场及流场的数值模拟[D]. 秦皇岛：燕山大学，2017.
[14] Ernst R，Perrier D，Brun P，et al. Multiphase electromagnetic stirring of low conducting liquids[J]. COMPEL-the International Journal for Computation and Mathematics in Electrical and Electronic Engineering, 2005, 24(1): 334-343.
[15] 李勇. 高频行波磁场增强低电导率液体传输的研究[D]. 北京：中国科学院大学，2019.
