THERMAL-HYDRAULIC ANALYSIS OF FERROFLUID LAMINAR FLOW IN TUBE UNDER NON-UNIFORM MAGNETIC FIELD CREATED BY A PERIODIC CURRENT-CARRYING WIRE

In this paper, a steady and laminar flow of ferrofluid (Fe3O4/Water) in a uniformly heated tube under the effect of non-uniform magnetic field arranged periodically along the tube is numerically analyzed using the finite volume method. The analysis sheds light on the flow pattern, Nusselt number, friction factor and the Performance Evaluation Criterion, at laminar flow regime (10(2) < Re < 10(3)) and for various magnetic numbers (Mn = 0, 2.83 . 104, 6.37 . 104 and 1.13 . 105). The obtained results show that the magnetic field generated by periodic arrangement of the wire pitches, forces the flow to behave periodically as a result of the counter-rotating vortices and its periodic fluctuations due the Kelvin body force distribution. As a consequence, the Nusselt number increased by up to 8 % comparing to the cases without magnetic field. Also, a noticeable low increment for the friction factor is noticed (0.5 %).