Numerical Simulation of Propulsion Systems Making Use of the Solar Wind

Abstract

Magneto Plasma Sail (Mini-magnetospheric plasma propulsion = M2P2) is one of propulsion systems which capture the momentum of the solar wind by a large artificial magnetic field arond a spacecraft. Magneto Plasma Sail produces a large magnetic field by injecting plasma into a small magnetic field from a spacecraft. The strong magnetic field near the spacecraft frozens in the plasma and inflates as the plasma expands. This magnetic field inflation is the essential technique for Magneto Plasma Sail. To understand the mechanism of the magnetic field inflation, the magnetic field inflation by the plasma injection is simulated in three-dimensional space using magnetohydrodynamics. The simulation results show that the ratio of the strength of inflated magnetic field to that of “original” (the initial magnetic field) depends neither on the ratio of the injected plasma dynamic pressure to the magnetic pressure nor on the dipole magnetic moment. To give an explanation to the structure of the inflated magnetic field, a simple theoretic model of the magnetic field inflation is proposed based on the frozen-in-field theorem and the magnetic flux conservation law.