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对一个以氮气为工作气体、在局域热力学平衡下的超声速电弧喷射器内等离子体流场进行了数值模拟。流动模型是耦合了电磁场的扩展Ｎ－Ｓ方程组。电场由电势方程近似反映，只考虑周向自感应磁场。数值方法中， 空间离散格式为中心差分， 用标量耗散模型抑制数值波动。用以经典四阶龙格－库塔法为基本迭代格式的时间推进方法求解控制方程组。电势的迭代计算采用多重网格加速收敛， 用隐式残值光滑技术改善收敛速度以及时间推进过程的稳定性。计算取得初步的成功： 电弧已经出现并可观察到电弧喷射器内的离解和电离状况以及化学不平衡、粘性等效应对流动过程的影响。
A numerical simulation of the plasma flow field in a supersonic arc jet with nitrogen gas as the working gas under local thermodynamic equilibrium was carried out. The flow model is an extended N-S system that couples electromagnetic fields. The electric field is approximately reflected by the potential equation, considering only the circumferential self-induced magnetic field. In the numerical method, the spatial discretization format is the center difference and the numerical fluctuation is suppressed by the scalar dissipation model. Solving Control Equations by Time Propulsion Method Based on Classical Fourth Order Runge - Kutta Method as Iteration Format. The iterative calculation of electric potential accelerates convergence with multiple grids, and the implicit residual smoothing technique improves the convergence speed and the stability of the time advancement process. Initial success was calculated: the arc had occurred and the effects of dissociation and ionization within the arc ejector and the effects of chemical imbalances, viscosities and other effects on the flow process were observed.