Blunt Body in Hypersonic Electromagnetic Flow Field

A combined experimental and computational effort has been devoted to investigate the interaction of a plasma counterflow jet and magnetoaerodynamic blunt-body phenomenon in hypersonic streams. The weakly ionized, counterflow jet generated by a plasma torch has a vibrionic temperature of 4400 K, an electron temperature around 20,000 K, and electron number density greater than 3 × 10^(12)/cm^(3). At a fixed injection stagnation pressure, the plasma injection actually increases drag above that of the room-temperature air counterpart due to a decreased mass flow rate at the elevated temperature. However, at the identical mass flow rate, the plasma injection reveals a greater drag reduction than the room-temperature air jet. It was found that the drag reduction is mostly derived from the viscous-inviscid interaction of the counterflow jet and thermal energy deposition. For the magnetoaerodynamic blunt-body experiment, the electromagnetic effect by an applied magnetic field from the blunt body is detectable, but its quantification remains elusive.