The program of experimental research regarding concentration of magnetic particles Fe3 O4 in ferrofluid for slide journal bearing lubrication

This paper presents the project of the test stand to determine the friction force, the relative eccentricity and temperature distribution m the slide journal bearing during the lubrication with ferrofluid or classic oil. The test stand is built on the basis of TUM 25 lathe's corps. There is the shaft with a diameter of journal d = 100 mm supported on two supports attached to the lathe's body. There is a sleeve in the housing with the electromagnets installed in the centre of this shaft. The housing of sleeve is loaded bv a transverse force with hydrostatic supports (cylindrical and flat one). Measurement of friction force is made by strain gauge force sensor Friction force is measured on the body shells. At the same time is performed measurement of both sleeve and journal displacements by four inductive displacement's sensor s and four whirl-stream ones to determine the relative eccentricity and displacement of sleeve axis towards oj the shaft axis. The slide bearing is supplied bv the ferrofluid which is thermatly stabilized in ultrathermostat. In the paper is shown particular plan for experimental research. These studies are intended to demonstrate the changes of relative eccentricity and temperature distribution in the bearing. Additionally are presented the changes of friction forces caused by the bearing surfaces shape and ferrolubricant with different concentrations of magnetic particles Fe3O4. The gap of slide bearing can be affected by the external longitudinal magnetic field with different ralues of magnetic field strength. The bearing may by loaded a transverse force varying stepwise, or continuously with values from a few to several thousand Newton. A/so, the rotational velocitv of Journal can be changed stepwise, or continuously from 0 to 6000 rpm using a programmable inverter