Stimulation of vigorous rotational flows and novel flow patterns using triaxial magnetic fields

Abstract

We have discovered that new flow patterns can be created by applying a dc field to the ac biaxial fields that are used to induce isothermal magnetic advection (IMA). IMA is a recently discovered fluid flow phenomenon that occurs in suspensions of magnetic platelets subjected to particular time-dependent, uniform, biaxial magnetic fields. IMA is characterized by the formation of emergent flow patterns called advection lattices. We find that a dc field can disrupt the antiparallel flow symmetry of the advection lattice and give rise to qualitatively new flow patterns, including vigorous rotational flows and a highly regular diamond lattice. The rotational flows are very robust and may have applications to heat transfer. The diamond lattice is an intriguing and challenging example of emergent dynamics. Both of these effects occur when the dc field is applied orthogonal to the plane of the biaxial field.