Relationship between Magnetic Field Interference and Electromagnetic Drag in Multicoil Magnetic Sails

In contrast to single-coil magnetic sails, multicoil magnetic sails do not require active attitude control and can retain a large drag force without increasing their power consumption by selecting the coil to be driven according to the attitude of the magnetic sail. However, determining the optimum position and direction of the magnetic axis from the infinite number of combinations is computationally intensive when using only a parametric study based on the magnetohydrodynamic analysis. The relationship between the magnetic field interference and drag is the basis for system studies of multicoil magnetic sails. Therefore, this paper clarifies the relationship between the magnetosphere shape induced by the arrangement of the coils and the drag force, and the relationship between the drag force and the region where the magnetic field is strengthened, using the three-dimensional magnetohydrodynamic analysis. Furthermore, this paper describes the application of the acquired knowledge to the design of multicoil magnetic sails.