| Abstract: | Continuous, three-dimensional control of the vorticity vector is possible
by progressively transitioning the field symmetry by applying or removing
a dc bias along one of the principal axes of mutually orthogonal
alternating fields. By exploiting this transition, the vorticity vector
can be oriented in a wide range of directions that comprise all three
spatial dimensions. Detuning one or more field components to create phase
modulation causes the vorticity vector to trace out complex orbits of a
wide variety, creating very robust multiaxial stirring. This multiaxial,
non-contact stirring is particularly attractive for applications where
the fluid volume has complex boundaries, or is congested. |