Transient elastohydrodynamic lubrication of finite line conjunction of cam to follower concentrated contact

Abstract

The paper presents a combined solution for multi-body dynamics of a modified cycloidal cam to flat follower with transient lubricated finite line contact conjunction. The solution to the dynamics of the valve train system is undertaken in the Euler frame of reference, which includes valve surge due to the non-linear behaviour of the spring. The elastohydrodynamic transient contact conjunction is analysed in each integration step time by simultaneous solution of the Reynolds' equation in space-time co-ordinates with the instantaneous elastic film shape equation, taking into account the generalized contact elasticity for finite line contact geometry. This approach, not hitherto reported in the literature, yields high generated pressures and thin films at contact extremities that govern wear and fatigue spalling performance of such contacts. Results show that the usual approaches in both quasi-static analyses and transient line contact solutions yield results that are not in line with actual prevailing conditions.