Specific features of non-Newtonian magnetorheological fluid flow in the workpiece-instrument gap of a polishing facility

摘要

>The model of magnetorheological polishing fluid flow has been developed in the form of a jet formed in the gradient magnetic field in the gap between the workpiece and the instrument of a polishing facility. The model allows one to determine the shape of the transverse and longitudinal sections of the jet and the pressure acting on the workpiece surface being polished, while accounting for the known configuration of the gap and magnetic field strength distribution. The appearance of the nose surf and the stern concurrent wave producing an additional pressure drop in the workpiece–instrument gap has been established. The solution of the Navier–Stokes equation in the approximation of lubrication for magnetorheological polishing fluid with boundary conditions accounting for the action of inertial forces has shown that in the inlet section of the gap the pressure drop is positive, and the velocity profile is almost flat near the workpiece, whereas closer to the outlet from the gap, the pressure falls below the atmospheric pressure. The pressure is maximum at the forward edge of the workpiece, as in the case of the well-known phenomenon of hydroplaning.