Water lubricated propeller shaft bearings are often used on modern ships because of its simplicity and low price. Working conditions of this kind of bearings are very specific. Loads are low because of bush length to shaft diameter ratio (L/D) usually equal four. Shaft sliding speeds are significant so there are good conditions for water hydrodynamic lubrication. Unfortunately, there are some serious problems with this kind of bearings. Due to low water viscosity hydrodynamic capacity is poor and lubrication film thickness is limited. Main task of conducted research was to increase hydrodynamic film capacity. The idea was to change typical bearing bush geometry and use hydrostatic support effect. In typical water lubricated bearings some lubrication grooves are very often recommended. Unfortunately groves designed in lower part of the bush have negative influence on hydrodynamic pressure field. The idea was to block lower grooves on water out-flow side and upper grooves on supply side. Thanks that hydrostatic support from the bottom appears. Furthermore thanks to upper groves it possible to reduce value of pressure field in the upper part of the bush, which effectively increases bearing capacity.
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