Generalized ferrofluid based lubrication equation and its application to porous journal bearing

Abstract

AbstractThis paper derived generalized ferrofluid based lubrication equation (based on the Shliomis model) from the basic theory for variable as well as uniform (transverse) strong magnetic fields. The variable magnetic field (VMF) is used because of retaining contributions from all magnetic terms of the Shliomis model. Moreover, it has an added advantage of generating maximum field at the required active contact zone in the bearing design system. Using above equation for variable and strong magnetic field, the case of porous journal bearing (PJB) is studied by considering equation of continuity in the film as well as porous region. The validity of the Darcy's law is assumed in the porous region. The modified Reynolds‐Darcy equation for PJB is derived by considering the effects of squeeze velocity, anisotropic permeability and slip velocity. The results show that dimensionless load‐carrying capacity increases with the increase of eccentricity ratio and the effect of magnetic field, and performed best for the decreasing values of the dimensionless permeability parameter in the x‐direction for a thin layer of the porous region. Moreover, the results are also compared with the behavior of different types of journal bearing designs discussed by different authors.