Influence of structure formation on heat transfer in magnetoelectrorheological suspensions

Abstract

Heat transfer in thin layers of magnetoelectrorheological fluids based on the γ-Fe₂O₃ and CrO₂ non-colloidal particles was studied in the presence of electric and magnetic fields. DC electric field causes significant rise of the heat transfer coefficient due to appearance of electroconvective vortexes in the volume of suspension. It is found that these vortexes can be effectively suppressed by applying magnetic field. AC electric field creates needle like structures lined up along the field in the volume of suspension. In the latter case the applying of magnetic field causes agglomeration of solid phase of suspensions in the vicinity of electrodes.

Keywords

magnetoelectrorheological fluid / heat transfer / structure formation / electroconvection

References

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