Tribological comparison of an optimum single and double slope design of the stern tube bearing, case study for a marine vessel

Abstract

In the present work, the optimal geometric parameters of a double slope aft stern-tube bearing are determined, for (a) maximizing the ‘effective pressure’ area between the bearing and the propeller shaft, and (b) minimizing the maximum local pressure exerted on the bearing surface. The aft stern-tube bearing design is modeled parametrically, taking into account the elastic shaft geometry. The computational approach used evolves from the solution of the Reynolds differential equation, which yields bearing operational parameters. The system is coupled to a general-purpose optimizer to calculate the optimum geometry based on two objective functions. Optimum designs for single and double slope bearings are calculated, and the performance parameters of these designs are compared for normal and extreme operational conditions.