Three-dimensional simulations of high-power magnetoplasmadynamic thrusters using the MACH3 code

In an effort to introduce MACH3 as a viable tool for investigation of 3-dimensional characteristics of magnetoplasmadynamic thrusters, preliminary simulations of a simplified geometry are performed. The purpose is to explore MACH3's capabilities as well as become familiar with its physical modeling. Two simulations at mass flow rates of .5 g/s and 1 g/s are examined. The 1 g/s case produces stronger currents than that of the .5 g/s case, and the currents propagate further downstream. The 1 g/s case also shows greater densities throughout the test section, which is to be expected, and lower temperatures further downstream. Both cases show azimuthal variations near the backplate, especially in current and temperature profiles, but become uniform downstream. The .5 g/s case appears to become azimuthally uniform further downstream than the 1 g/s case, which may indicate that it has not yet reached a steady state condition. As a point of comparison, a 2-dimensional MACH2 model is invoked with identical conditions and geometry at a mass flow rate of 1 g/s. Comparisons between the 3-dimensional and the 2-dimensional, axisymmetric flows exhibit differences both qualitatively and quantitatively. These may be result of the additional dimension in combination to uncertainties related to the 3-D modeling. The results, while within a simplified geometry, demonstrate some of MACH3's capabilities as well as identify some challenges.