An analysis of sector-shaped thrust bearings operating in the transition regime

Abstract

The purpose of this study was twofold: (i) to introduce a modified mixing length expression of Reynolds stress in transition and turbulent lubrication theory; (ii) to determine the performance characteristics of sector-shaped thrust bearings when operated in the transition regime taking into account the inertia effects. A new model of Reynolds stresses for transition-turbulent theory is proposed. The approach relies on Prandtl's mixing length theory and a modified Van Driest mixing length formula which accounts for the effect of the shear stress gradient in thin film lubrication. The mixing length model is used to analyse turbulent planar and non-planar flows. Turbulent coefficients obtained from the non-planar cases are used to analyse the sector-shaped thrust bearing in the transition region, taking into account the convective inertia forces and centrifugal forces. Bearing performance characteristics such as pressure distribution, load carrying capacity, pressure centre and inlet flow rate are calculated.