Global MHD Simulation of the Magnetic Sail Expansion by Plasma Injection

Large scale strong magnetic field technology (namely magnetic sail) has important application value in space radiation protection and power propulsion. This paper mainly studies the key technology of large scale magnetic sail generation in low earth orbit (500 km, LEO). Based on the 3-D magnetohydrodynamics (MHD) numerical simulation model, the expansion phenomenon of satellite dipole field (Similar to magnetosphere, namely mini-magnetosphere) caused by plasma injection is studied. The numerical simulation results show that the dipole magnetic field carried by the satellite will continuously expand with the injection of plasma, and the attenuation of its magnetic field strength with distance will change from r−3 to r−2~r−1. In LEO magnetosphere region, its scale can expand more than 200 m. There are two main physical mechanisms for the expansion of the mini-magnetosphere: (1) the continuous enhancement of plasma hot pressing; and (2) the ring current structure formed by drift.