Influence of magnetic fluids' cohesion force and squeeze dynamic effect on the lubrication performance of journal bearing

Abstract

Using the magnetic fluids containing polymer additives as the lubricant with couple stress, this article first develops the lubrication model of the journal bearing considering the couple interaction between its squeeze dynamic effect and its rotating effect. The effects of the squeeze dynamic effect of journal bearing, magnetic fluids' cohesion force, and magnetic fluids' couple stress on the lubrication performance of journal bearing (the load-carrying capacity (S) and its attitude angle (ψ), the friction coefficient (Cf(R/c)), and the side leakage (Q)) has also been studied. The results above show that the maximum dimensionless film pressure (Pmax) along the bearing centerline increases as the increase of the squeeze dynamical effect parameter (q), magnetic fluids' cohesion force coefficient (γ), and magnetic fluids' couple stress parameter (L∗); ψ decreases as the increase of q, the decrease of γ, and the increase of L∗; S increases as the increase of q, γ, and L∗; Cf(R/c) decreases as the increase of q, γ, and L∗; Q decreases as the decrease of q, the increase of γ, and the increase of L∗.