Parameter Research of an MHD Controlled Inlet

Abstract

When flight Mach number is lower than the design value both MHD (magneto-hydrodynamic) accelerator and generator can be used to improve the performance of the scramjet inlet. MHD controlled inlet of accelerator mode was analyzed in this paper. The magnetic field has components perpendicular and parallel to the flow direction. The computational model consists of the Euler or N-S equations coupled with the electric-magnetic source terms, ideal gas state equation, Maxwell equations and the Generalized Ohm’s law. The influence of some key parameters on the performance of the inlet was analyzed. The results show that at a proper choice of other parameters, increase of the magnitude of magnetic induction will increase mass capture and compression, due to irreversible effects total pressure will decrease. The angle of the magnetic induction and the x coordinate of the MHD interaction region have optimal values to get the maximal mass capture. The analysis also shows that the increase of mass capture and pressure is mainly due to the MHD interaction near and below the cowl lip region. A group of optimized parameters has been chosen to calculate the flow field, the results show a considerable improvement of the inlet air mass capture and pressure rise while the loss of total pressure is limited to a reasonable extend. Considering about the viscous effects the benefit of MHD controlled inlet is more obvious, the mass flow rate, pressure rise, and total pressure recovery ratio can all be increased.