Abstract
The research conducted here aims to expand the operating load range and offset manufacturing costs of tapered-land hydrodynamic bearings by creating deflecting bearing sectors through use of selective laser sintering. The motivation of this study comes from the fact that the required taper depth of tapered-land hydrodynamic thrust bearings is determined before manufacturing and is dependent on the expected operating axial loads. If the applied load exceeds the range for which the taper depth was selected for, the bearing will not operate efficiently, and an increased rate of wear will occur. Here, the bearing sectors are designed to deflect during applied loading; this acts as a self-governing device that allows the bearings to operate efficiently over a wider range of applied axial loads compared to their traditionally manufactured counterparts. Experimental analysis was conducted on selective laser sintered aluminum alloy tensile samples to obtain necessary material properties. Three bi-directional bearing sectors having an initial taper height of 88.9 μm were modeled with internal features that allow and limit deflection during pressure generation and bearing operation. The internal features can only be manufactured using additive manufacturing techniques such as selective laser sintering. A mechanical analysis was conducted in ABAQUS/Standard using the material data captured from the tensile tests to show that the bearing sectors deflect 38.8 μm, 64.1 μm, and 76.8 μm due to in-service film pressure distributions. The results of this analysis provide evidence that additive manufacturing can be used to expand operating loads and offset costs of traditional subtractive manufactured hydrodynamic bearings through tailoring of internal structures during manufacturing.
