霍尔推力器磁场位形及其优化的数值研究

Numerical study on Hall thruster magnetic configuration and its optimization

基于麦克斯韦方程,在轴对称假设下建立了霍尔推力器磁场的数学模型.用有限差分方法对模型进行了离散.给出了数值求解模型的迭代法.通过对模型的数值求解,得到了相应的数值结果.通过对所得数值结果的分析,研究了磁场线圈电流变化对霍尔推力器磁场位形的影响.通过调整磁场线圈电流的大小找到了理想磁场位形.研究表明,对于理想磁场位形,内通道的磁镜比在3—3.5之间,外通道的磁镜比在0.4—0.9之间;增加磁场线圈的电流,出口的磁场强度随着增加,但不能增加磁镜比.通道内部的磁场强度几乎不随着磁场线圈电流的变化而变化.

Based on Maxwell＇s equations,under axis-symmetric assumption,a mathematical model of the magnetic field of a Hall thruster is established. A finite difference method is used for discretizing the model. An iterative method for numerically solving the model is given. The numerical results are obtained. From analysis of the results,the effect of the current in the magnetic field coils on the magnetic configuration of a Hall thruster is investigated. Through adjusting the current,the ideal magnetic configurations are found. It was shown that,for ideal magnetic configuration,the magnetic mirror ratio in the inner channel is between 3 and 3. 5,and the magnetic mirror ratio in the outer channel is between 0. 4 and 0. 9. With the increasing of the current in the magnetic field coils,the magnetic field at the exit of the channel increases,but the magnetic mirror ratio cannot be increased. The magnetic field in the inner channel hardly changes with change of the currents in the magnetic field coils.