Rotation of ferrofluid drop due to inclined oscillating magnetic field

Jyun Chen Shih^1*, Hong-Yu Chu¹

¹Department of Physics, National Chung Cheng University, Chia-Yi, Taiwan

* Presenter:Jyun Chen Shih, email:a3525361@gmail.com

Ferrofluid is a kind of liquid that can be controlled by the external magnetic field which is because of the colloidal particles Fe₃O₄ suspended in the carrier fluid. The dynamics of ferrofluid drop at time-dependent magnetic field is discussed. The kerosene-based ferrofluid drop is put in the saline water which is immiscible with ferrofluid. Normally, the ferrofluid drop is stretched and shrunk along the axial symmetric direction of the time-dependent magnetic field. By using the Helmholtz coils to generating the time-dependent magnetic field with inclined angle, it is found that the ferrofluid drop not just oscillates along the direction of magnetic field but also rotates. We show that the rotation of ferrofluid drop depends on the frequency of magnetic field and the inclined angle of the Helmholtz coils.

Keywords: Ferrofluid, Rotating drop, Time-dependent magnetic field