Constitutive equation of MR fluids

Abstract

Magnetorheological(MR) fluids are intelligent materials whose mechanical properties will change with the magnetic field strength. Based on this behavior, the MR fluids can be used in wide practice fields. The constitutive equation is the most important problem of research of MR fluids. The mechanical experiments of a sort of MR fluids were conducted. By the Maxwell model, the visco-plastic behavior of magnetorheological fluids was discussed by a simple mechanical model. Then a new constitutive model was developed. The parameters of this model were investigated. The relation of the stress of MR fluids and the magnetic field strength was analyzed by this equation. The agreement of calculated curves with the experimented ones are very satisfactory. The results show that this constitutive model can be used to explain the mechanical properties of the MR fluids.

Keywords

MR fluids / shear stress / visco-plastic / mechanical model

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