4th WCSET-2015 at Japan
Mechanical Engineering:
Title:
Characterizing Transient Thermomagnetic Flows in a
Thermomagnetic Pump
Authors:
Upasana Panigrahi, Ranjan Ganguly, Amitava Datta
Abstract:
The synergetic effect of the external magnetic field and
the temperature gradient in the fluid constitutes a
thermomagnetic pump. The device works with temperature
sensitive ferrofluid as working medium under an
externally imposed magnetic field and temperature
gradient that drives the fluid in extremely small volume
and small operating head. It has been pointed out in the
literature that thermomagnetic convection under a
gradient magnetic field becomes stronger at small length
scale. This finding, coupled with the need for reliable
pumping arrangement for microfluidics device, has
generated recent interest in harnessing thermomagnetic
convection for microfluidic pumping in a contact-less
manner. Although there has been a few recent works on
the steady state behaviour of thermomagnetic pumps,
transient behaviour of the thermomagnetic flows in
relevant applications have not been investigated in
detail. In this paper, the thermal behaviour of confined
thermomagnetic pump under shut-off condition is studied.
Experimental investigation shows that upon sudden loss
of field in a shut-off condition, a quick rise in
temperature at the inlet and outlet sections of a
thermomagnetic pump is observed. To understand the
underlying principle, numerical simulation of a
representative confined enclosure has also been done.
Keywords: Thermo-magnetic
pump, Ferrofluid, Thermo-magnetic convection; MEMS;
Kelvin body force
Pages:
145-153