Experimental Investigation of Frictional Force in a Hydrodynamic Journal Bearing Lubricated with Magnetorheological Fluid

Abstract

Variations in frictional force developed in the journal bearing lubricated with Magnetorheological (MR) fluid was investigated. Also, a comparative study was conducted between MR fluids and SAE15W40 grade engine oil on the performance characteristics. A test bearing set-up was developed to accommodate MR fluid film with provision for varying magnetic field. MR Fluid was formulated by dispersing electrolytic grade micron sized iron particles in silicon oil base fluid in 0.3 volume fraction. The results of the experimental testing indicated an increase in frictional force with increasing excitation current in the electromagnetic cores of journal bearing for similar loads and speeds in comparison to plain engine oil; the presence of MR fluid causes an increase in viscosity in comparison to plain engine oil and thus holds a great potential to increase the load carrying capacity of the journal bearing.