Performance of hydrodynamic lubrication journal bearing with a slippage surface

Purpose The aim of this paper is to propose a design idea for an infinite journal bearing with the optimized slip zone on the bearing sleeve surface. Design/methodology/approach The approach is to use finite element analysis and the quadratic programming algorithm to study the performance of the journal bearing with a slip zone on the sleeve surface. The fluid film pressure and slip velocity can be obtained in one solution step. Findings A journal bearing with a slip zone on the sleeve surface produces many different advantages over the traditional journal bearing. Even in a parallel sliding gap there is still a considerable large load support, but a very low friction drag. The effect of the enhancement of such a slip wedge on the journal bearing performance is much greater at a small eccentricity ratio than at a large eccentricity ratio. Numerical analyses indicate that the location and size of the slip zone greatly affect the journal performance. When the eccentricity ratio ϵ =0.8, the maximum load support is increased by ∼19 per cent and surface friction coefficients reduced by ∼35 per cent and ∼42 per cent at shaft and sleeve surfaces, respectively. Originality/value The paper shows how the present concept can be used to design not only a journal bearing but also a thrust bearing with a slip wedge.