  In this paper, the effectiveness of electromagnetic forces on controlling the
motion of a sedimenting elliptical particle is investigated using the immersed
interface-lattice Boltzmann method (II-LBM), in which a signed distance
function is adopted to apply the jump conditions for the II-LBM and to add
external electromagnetic forces. First, mechanisms of electromagnetic control
on suppressing vorticity generation based on the vorticity equation and vortex
shedding based on the streamwise momentum equation are discussed. Then,
systematical investigations are performed to quantify and qualify the effects
of the electromagnetic control by changing the electromagnetic strength, the
initial orientation angle of the elliptical particle, and the density ratio of
the particle to the fluid. To demonstrate the control effect of different
cases, comparisons of vorticity fields, particle trajectories, orientation
angles, and energy transfers of the particles are presented. Results show that
the rotational motion of the particle can be well controlled by appropriate
magnitudes of electromagnetic forces. In a relatively high solid to fluid
density ratio case where vortex shedding appears, the sedimentation speed can
increase nearly 40\% and the motion of the particle turns into a steady descent
motion once an appropriate magnitude of the electromagnetic force is applied.
When the magnitude of the electromagnetic force is excessive, the particle will
deviate from the center of the side walls. In addition, the controlling
approach is shown to be robust for various initial orientation angles and solid
to fluid density ratios.
