Mixed lubrication characteristics of multi-layer composite structure water-lubricated stern bearing considering fluid–structure interaction and journal misalignment effects

In order to solve the problem of uneven pressure distribution in traditional water-lubricated bearings, a multi-layer composite structure water-lubricated bearing is proposed in this paper. Considering the fluid–structure interaction and journal misalignment effects, a mixed lubrication model of multi-layer composite structure water-lubricated bearing is established. Based on the aforementioned model, first, experimental tests are conducted to verify the accuracy of the model. Second, the lubrication characteristics of multi-layer bearing and single layer bearing are compared. Finally, the effects of external load, journal rotational speed, and aspect ratio on the pressure, film thickness, and friction coefficient of multi-layer composite structure water-lubricated bearing are investigated. The research results show that the multi-layer composite structure water-lubricated bearing can improve pressure distribution uniformity, enhance minimum film thickness, and reduce friction. By studying the lubrication characteristics of multi-layer composite structure water-lubricated bearing under different parameter conditions, it provides theoretical support for the structural optimization of water-lubricated stern bearings.