3D Hybrid Simulation of Pure Magnetic Sail on Ion Inertial Scale in Laboratory

抄録

Magnetic sail is a propellantless propulsion system used in space, which is capable of generating a propulsive force by the interaction between the magnetic field generated by a hoop coil and the solar wind plasma flow. Three dimensional hybrid (ion particles and electron fluid) particle-in-cell (PIC) simulation and scale-model experiment are performed to investigate the characteristics of the plasma flow around a magnetosphere on the ion inertial scale where an ion gyro radius rLi is comparable to the representative size of magnetosphere L. It is found that the dark region around magnetospheric boundary appearing in the experimental photograph corresponds to the region where the plasma density increases due to the plasma trapped by the magnetic field. The induced current which is both perpendicular to the plasma flow and the magnetic field also increases in the magnetospheric boundary region hence this region coincides with the magnetopause current layer. The width of the magnetopause current layer has a good agreement between the numerical simulation result and experimental result. Also, the predicted thrust value of 0.34 ± 0.01 N obtained by the hybrid simulation agrees well with the experimental result when numerical simulation is carried out by considering the ion-neutral collision effect. The hybrid PIC simulation carried out without considering the collisional effect gave a thrust value of 0.4 ± 0.01 N (increasing by a factor of 1.3), which can be applied to the thrust evaluation of the magnetic sail in a collisionless interplanetary space.