Configuration-dependent field effect on horizontal convective heat transfer in a quasi-one-dimensional magnetic fluid

We report our study on field effect on horizontal convective heat transfer in a quasi-one-dimensional magnetic fluid in different temperature and field gradients orientation, where the magnetic boy force and the temperature gradient are perpendicular to gravity. Both gravito-thermal and magneto-thermal convections happen when the fields are applied. It was found the magnetic field-induced magneto-thermal flows enhances the gravito-thermal convection when the temperature gradients and field gradients are parallel, and suppresses it when the two gradients are antiparallel, where the single convection roll in zero field was separated into two localized rolls at the two ends of the sample cell. The drastically different flow patterns explain the different field effect on heat transfer in two configurations, which is consistent with the different direction of magnetic body force. It was also found when the field exceed the critical point, the magneto-thermal convections is dominated in the fluids. This novel phenomenon demonstrates new path to energy conversion and important applications in thermal management of electronic device and electric vehicle, and energy transfer devices.