Experiments and analysis for rheological properties of MRF

Abstract

The work principle of flat-plate structure under shearing mode is expounded based on a vertical type rheometer for MRF which combined data acquisition with treatment and result display. The formula to calculate shearing stress is deduced. Based on different recipe for MRF, experiments under different working gap length were done by altering the intensity of magnetic field. The rheological model for MRF was established and the relationships between shearing stress, viscosity and magnetic field intensity were deduced. Experiments indicate that MRF has the flowing characters: with an increase of the magnetic induction and the nominal shear rate, the shear stress of MRF increases. However, as the working gap decreases, the shear stress increases. MRF has shear thinning property under magnetic field.

Keywords

magneto-rheological fluid / constitutive equation / rheometer / experiment

References

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