Sensitivity Studies for the Shallow-Pocket Geometry of a Hydrostatic Thrust Bearing
Hydrostatic thrust bearings have been the object of considerable research for many years. The attention that these bearings have received is primarily due to the important role they play in the design and operation of heavy equipment. In this role, the hydrostatic thrust bearing is often considered to be the “Achilles heel” of the total machine system as failures result in catastrophic difficulties and expensive repairs. The objectives of this research are to examine the nuances of designing a hydorstatic thrust bearing using a shallow pocket as opposed to the more traditional deep pocket design. By using a two-dimensional model for this geometry, the basic features of the shallow pocket design are extracted in closed-form and behaviors that would be expected in the three-dimensional setting are identified. In this research, a single dimensionless parameter is used to describe the influence of the bearing speed under laminar flow conditions. The principal results of this research are closed-form expression that describe the load carrying capcity of the bearing, the tilting moment exerted on the bearing by a skewed pressure distribution, and the volumetric leakage of the bearing. Sensitivity studies are conducted using these results and the influence of small perturbations of the pocket depth are identified for bearings with different pocket widths. These results are discussed and conclusions are itemized in the final section of the paper.