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The magnetorheological fluids are classified as smart materials with controllable rheological properties. The fast growing application of magnetorheological fluids in recent years has increased the demand for simulation and modeling of these fluids. From the invention of magnetorheological fluids up to now, many experimental and also theoretical investigations have been carried out to study these types of smart materials; also many attempts have been made to formulate and simulate their behavior. The aim of this investigation is to present a review on the different models and simulation methods that were applied in the studying of magnetorheological fluids. In this study, the different simulation methods of magnetorheological fluid have been categorized into two general approaches: continuum and discrete phase approaches. The different rheological and structural models of magnetorheological fluids in continuum approach have been summarized in this study. The computational framework of discrete approach and the basic models for magnetorheological fluid in this approach are also discussed.

In this study, the stability and rheological properties of a suspension of carbonyl iron microparticles (CIMs) in silicone oil were investigated within a temperature range of 10 to 85 °C. The effect of adding two hydrophobic (stearic and palmitic) acids on the stability and magnetorheological effect of a suspension of CIMs in silicone oil was studied. According to the results, for preparing a stable and efficient magnetorheological (MR) fluid, additives should be utilized. Therefore, 3 wt% of stearic acid was added to the MR fluid which led to an enhancement of the fluid stability over 92% at 25 °C. By investigating shear stress variation due to the changes in the shear rate for acid-based MR fluids, the maximum yield stress was obtained by fitting the Bingham plastic rheological model at high shear rates. Based on the existing correlations of yield stress and either temperature or magnetic field strength, a new model was fitted to the experimental data to monitor the simultaneous effect of magnetic field strength and temperature on the maximum yield stress. The results demonstrated that as the magnetic field intensified or the temperature decreased, the maximum yield stress increased dramatically. In addition, when the MR fluid reached its magnetic saturation, the viscosity of fluid depended only on the shear rate.

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In this study, the effect of adding magnetizable and non-magnetizable nano particles (magnetite and fumed silica) to magnetorheological fluids was investigated experimentally. The results showed a great increase up to six times in magnetorheological effect when using magnetite in comparison to nano particle–free magnetorheological fluids. On the other hand, adding non-magnetizable silica made the suspension stable for more than 2000 h by somehow increasing magnetorheological effect. Herschel–Bulkley model fitted the experimental data well and shear thinning behaviour was observed in all synthesized magnetorheological fluids.