Hypersonic Magnetohydrodynamic Generator Based on Electron-Beam-Generated Ionization

In order to comprehend the performance of hypersonic cold-air MHD power generators with ionization by electron beams,the flow phenomena of a rectangular Faraday type MHD generator with segmented electrode were simulated using three dimensional MHD five-equation model associated with low magnetic Reynolds assumption and a simple model of beam-generated ionization.The effects of the power spent on ionization and the intensity of magnetic field on the performance of the generator were investigated,obtaining the number density of electrons and electrical conductivity formed by the ionization under different ionization spent.The results show that electron beams are capable of generating an adequate conductivity in cold air.When the loading factor is 0.5,electrical efficiency is substantially maintained at between 0.5-0.6,and the intensity of magnetic field has no effect on electrical efficiency.When power spent on ionization is 0.06MW/m3,0.6MW/m3,6MW/m3,30MW/m3,respectively,the conductivity σ(S/m) is 0.28,0.9,3,7,27,respectively.When power spent on ionization is 30MW/m3,the energy extraction rate is 26% and the electrical efficiency is 66%,close to the optimal performance of the generator,corresponding the intensity of magnetic field of 10T.