Abstract
Effect of magnetic field direction on forced convective heat transfer of magnetic fluid flow in a rectangular duct was investigated experimentally. Magnetic fields were applied to magnetic fluid flow in three directions, which were an axial direction, a parallel direction and a vertical direction against the heat transfer direction. Reynolds numbers based on hydraulic diameter and bulk mean velocity were set at about 980 for laminar flow and about 6700 for turbulent flow. In the case of laminar flow, heat transfer was enhanced in the vertical direction and slightly enhanced in the axial direction, but hardly changed in the parallel direction. In contrast, in the case of turbulent flow, heat transfer was suppressed in all directions. The suppression level in vertical and parallel direction is similar, but the suppression in axial direction is much weaker than those in other directions. Moreover, in order to discuss the heat transfer characteristics, the velocity distribution was also measured by an ultrasonic technique.
