磁场作用下平行平板内导电流体的流动稳定性

doi:10.16182/j.issn1004731x.joss.201708016

摘要/Abstract

摘要： 采用非正则模态稳定性分析方法,对法向磁场作用下导电流体在导电平行平板内的流动稳定性进行了数值模拟,分析了磁场对流动稳定性的影响。结果表明,哈特曼数Ha较大时(Ha>9),上、下两个哈特曼边界层基本上各自独立,互不影响;哈特曼数Ha较小时(Ha<9),上、下两个哈特曼边界层距离较近,存在着一定的相互作用,并影响着整个流场的稳定性。平板导电时的扰动增长特征与平板绝缘情形下基本类似;但在平板导电条件下,磁场对扰动的抑制效果更明显。

关键词: 导电平板, 哈特曼边界层, 稳定性, 非正则模态, 数值模拟, 流动

Abstract: The stability of conducting fluid flow in a channel under a vertical magnetic field was simulated by non-normal modal stability analysis. The perfect conductivity assumption of the channel wall was employed in the model, and its effect on the stability problem was considered. The results show that when the Hartmann number Ha is larger than 9, the two opposite Hartmann boundary layers are essentially independent of each other; however, when the Hartmann number Ha is smaller than 9, there are still residual interactions between the two opposite Hartmann boundary layers, which has influences on the stability of the flow. Furthermore, the growth of disturbances in the present case is similar to the one with insulating walls. When the walls are conducting, the suppression effect of the magnetic field on the disturbances is more significant.

Key words: conducting walls, Hartmann boundary layers, stability, non-normal modal, numerical simulation, flow

中图分类号:

O361.5

董帅, 刘立帅, 叶学民. 磁场作用下平行平板内导电流体的流动稳定性[J]. 系统仿真学报, 2017, 29(8): 1762-1771.

Dong Shuai, Liu Lishuai, Ye Xuemin. Stability of Electrically Conducting Fluid Flow in Channel under Magnetic Field[J]. Journal of System Simulation, 2017, 29(8): 1762-1771.

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