In recent experiments, it is found that an annular boss anode structure can be used to adjust the arc anode attachment mode, which is expected to be beneficial for improving the anode heat transfer. To understand the effect of annular boss structure on the arc anode attachment, two-dimensional axisymmetric numerical simulation is performed based on a two-temperature chemical non-equilibrium model. The results show that the existence of the annular boss changes the distribution of electric field along the anode surface, and then the arc is attracted to the annular boss because of the enhancement of the nearby electric field intensity. This results in a decrease in the peak current density and a change in its radial distribution in the anode arc attachment region. As a result, the magnitude and direction of the Lorentz force are also changed, acting to suppress the formation of the anode jet. Compared with the case of planar anode, the heat flux of anode with annular boss decreases significantly due to the diffusive arc attachment, which results in significant reduction of the maximum anode temperature. Besides, the effect of the size of annular boss on arc anode attachment behavior has been investigated and the numerical results show that a reasonable choice of inner diameter is important for the formation of diffusion-type anode arc attachment.

在最近的实验中，发现可以采用环形凸台阳极结构来调整电弧阳极的附着方式，有望有利于提高阳极传热。为了解环形凸台结构对电弧阳极连接的影响，基于两温化学非平衡模型进行二维轴对称数值模拟。结果表明，环形凸台的存在改变了沿阳极表面的电场分布，由于附近电场强度的增强，电弧被吸引到环形凸台上。这导致峰值电流密度的降低和阳极电弧附着区域中其径向分布的变化。结果，洛伦兹力的大小和方向也发生了变化，用于抑制阳极射流的形成。与平面阳极相比，环形凸台阳极的热通量由于扩散弧的附着而显着降低，从而导致最高阳极温度显着降低。此外，研究了环形凸台尺寸对电弧阳极附着行为的影响，数值结果表明，合理选择内径对扩散型阳极电弧附着的形成很重要。