Modeling of ferrofluid-based microvalves in the magnetic field created by a current-carrying wire

The paper deals with a ferrofluid-based valve which can open and close the channel formed by two coaxial cones and a cylinder in the magnetic field of a straight current-carrying wire. Numerical modeling of the ferrofluid valve behaviour for different values of ferrofluid volume, pressure drop and current in the wire is done when the ferrofluid wets surrounding solid boundaries. It is shown that the presence of limiting cones allows the ferrofluid valve to sustain a pressure drop at high enough currents. The maximum pressure drop and the needed current can be obtained for each possible ferrofluid volume. (C) 2017 Elsevier B.V. All rights reserved.