MHD reaction wheel for spacecraft attitude control: Configuration and lumped parameter model

A novel actuator for spacecraft attitude control with liquid flywheel is presented. The main characteristic of this new concept of a reaction wheel is that a conductive liquid rather than a solid mass is accelerated to change the angular momentum of the equipment and, as a consequence, to provide the torque to the spacecraft. The conductive liquid inside an annulus with rectangular cross section is accelerated using the Lorentz force originates from the interaction between an electric current flowing through the fluid and a magnetic field. This paper proposes two suitable configurations of the device and a lumped parameter model based on Magneto-Fluid Dynamics set of equations under the hypothesis of low Magnetic Reynolds. The lumped parameter model is addressed to one of the two configurations considered more suitable for space application.