ABSTRACT

Magnetorheological (MR) fluids are suspensions of magnetizable particles. Under the application of an external magnetic field, these particles self-arrange in percolating structures that provide the suspension with a field-controllable yield stress. Due to the high-loadings and strong magnetic non-linear behavior of the employed particles, the yield stress of MR fluids is affected by multibody, multipolar and non-linear effects. We present a method, based on the Finite Element Method, to compute the yield stress including all those effects. Contrary to current models based on the dipolar approximation, the proposed method is able to predict quantitatively the yield stress for wide intervals of applied fields and particle concentrations.