A new modified model for the rheological properties of magnetorheological fluids based on different magnetic field

摘要

Magnetorheological (MR) fluids presents obvious rheological properties under external magnetic fields. A rotational rheometer was adopted to investigate the relationship between shear stress and shear rate of different volume fractions MR fluids under different applied magnetic field strengths, which is one of the most important indicators of rheological property of MR fluids. Shear stress increases with the increasing of applied magnetic field and particles volume concentration. While, MR fluid shows the pseudo-plastic fluid behavior when the volume fraction was 28% without magnetic field. Different constitutive models (i.e. H-B model, S-S model and a modified model used to analyze flowing law of MR fluids) were employed, respectively. Results show that the modified flow model fits well with experimental results as a whole compared to other models, and the modified model is more simple and effective.