Models of viscosity characteristics η=η(b) of ferro-oil with different concentration of magnetic particles in the presence of external magnetic field

The purpose of this article is to determine, identify and describe the viscosity characteristics of the ferro-oil with different concentrations of magnetic particles in the presence of an external magnetic field interaction. These characteristics are defined in the context of magnetic induction changes. These rheological tests were performed on a Physica MCR 301 rheometer. It was used a measuring system ‘plate to plate’ type which was armed with magneto-rheological research system MRD 180/1T. The tests were performed for the selected temperature of the medium i.e. 90°C, the shear rate θ changes were carried from 0 to 1000 1/s. Changes of the magnetic field intensity value were ranged from 0 to 500 mT. The selected concentrations of magnetic particles in a ferro-oil were 1%, 2%, 4%, 6% and 8% and the tested ferro-oil was product of FerroTec of Unterensingen (Germany), which is a mixture of colloidal mineral motor oil Penzzoil’s LongLife Gold's SAE 15W-40 with Fe3O4 magnetic particles and the surfactant. Analyses of the results, identify and matching characteristic were calculated using STATISTICA software. It has been proposed three categories of functions mapping the waveforms of the results obtained experimentally: the exponential function, logarithmic with basis of the normal and the polynomial function.