Abstract
This paper numerically investigates the static characteristics of hybrid (air/water) hydrostatic journal bearings and the displacement of the shaft supported by these bearings. The system treated consists of four identical hybrid bearings and a rotating shaft. Each bearing can use either air or water as the operating fluid. In the calculations, the misalignment due to an offset load is taken into account. The Reynolds equation and the equilibrium equations of force and moment are calculated simultaneously, using Newton-Raphson method. As a result, it was found that the load capacity is largely improved by changing the operating fluid of only the nearest bearing to the offset load from air to water, in comparison with that in the case where air is supplied to all of four bearings. In addition, the load capacity in the case where water is supplied only to one bearing shows almost the same value as that in the case that all of them are lubricated by water though the shaft behavior such as the attitude angle is greatly changed.
