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The upgraded nonequilibrium magnetohydrodynamics (MHD) solver MACH2 is applied to the modeling of an annular, Hall-type MHD generator that can be employed upstream of a turbojet engine at freestream conditions corresponding to Mach 5 flight at an altitude of 20 km. The simulations demonstrate the feasibility of converting inlet kinetic power to storable electric power on aircraft traveling at supersonic to hypersonic speeds. Using ionization provided by electron-beam guns and a radial magnetic field B = 3T, the generator is shown to produce a maximum of 4.8 MW of electric power while reducing the total kinetic power of the flow by 31%. Optimizing the loading parameter, K*Load, across the electrodes demonstrates that the generator could produce 1.54 MW of excess electric power that can be stored and used for on-board power requirements. Additionally, the reduction in flow kinetic power results in an increase in static pressure of 30% and a reduction in stagnation temperature of 3% at the turbojet’s compressor inlet, aiding the subsequent process of combustion and allowing for operation of the turbojet at higher velocities.

The time-dependent, 2[1/2]-dimensional, axisymmetric, magnetohydrodynamics (MHD) solver, MACH2 has been upgraded to include the effects of nonequilibrium air chemistry in order to properly model weakly ionized flows over high-speed vehicles. The thermochemical model was subjected to several validation cases such as comparisons to the experimentally deduced shock stand-off distance of nitrogen flow over spheres, the shock stand-off distance of spheres fired into air in a ballistic test facility, and the electron number density on the surface of the Ram-C re-entry experiment. Furthermore, the magnetic induction equation has been upgraded with new verified models that compute the Hall effect, ion slip terms, and an applied axial electric field. Finally, simulations of an idealized MHD electrical power generator are compared with existing analytic solutions, demonstrating the applicability of the improved numerical code to model, analyze and design MHD power generators onboard high-speed vehicles.