A fixed geometry hybrid thrust bearing is investigated with three different supply orifice diameters. The test rig uses a face-to-face thrust bearing design, with the test bearing acting as the rotor loading mechanism. A hydraulic shaker applies the static axial load, which is reacted by a second thrust bearing. The rotor is supported radially by two water-lubricated fluid film journal bearings and is attached to a 30,600 rpm motor via a high speed coupling with very low axial stiffness. Thrust bearings with three different orifice diameters (1.63, 1.80, and 1.93 mm) are tested for a range of supply pressures, fluid film thicknesses, and rotational speeds. The water-lubricated test bearings have eight pockets, with feed orifices located centrally in each pocket. Experimental results are comparted to predictions found using bulk flow model HYDROTHRUST. Analysis of the data reveals generally good agreements between predictions and measurements. Thrust-bearing inlet supply and inner radius flow rates all decreased with decreasing orifice diameters and bearing axial clearances. In most cases, the bearings with larger orifice diameters exhibit higher recess pressure ratios, operating clearances, and flow rates. The largest orifice diameter configuration does not display higher recess pressure ratios or operating clearances at high speeds for some supply pressures, but it does continue to require additional lubricant flow rate compared to the smaller orifice bearings. In these cases, the results are not reflected in predictions, which otherwise correlate very well with experimental measurements. Estimations of static loading axial stiffness are obtained using experimental results. An optimum hybrid thrust bearing orifice diameter will depend on the conditions of individual applications. Larger orifices generally provide larger operating clearances and higher stiffnesses, but also require higher flow rates. For most applications, a compromise of bearing performance parameters will be desired. The test results and comparisons presented will aid in sizing orifice diameters for future hybrid thrust bearing designs.

The present work focuses on the test method for the investigation of combined journal-thrust bearings. In simple applications, radial or thrust bearings are separated physically and can be considered as stand-alone machine elements. These can each be dimensioned by established calculation models. In compact designs, combined bearings must be used due to space savings. In this case, the bearing parts are present as a unit in which the axial part is supplied with lubricant from the radial part. If the bearing parts are treated separately, the oil outlet temperature of the radial part can serve as the input variable for the axial part. In this case, both the coupled thermal conduction between the running surfaces through the material and the pressure interaction between the two bearing parts are neglected. The thermal coupling of the bearing parts leads to an overall higher thermal load. The pressure interaction affects the respective volume flow, which also has a significant influence on the respective bearing temperatures. The development and validation of a simulation program required accompanying extensive measurements on the real bearing. For this purpose, the development of a suitable test bench for applying a combined radial and axial load is to be presented in this paper. In addition, the measurement procedures will be discussed, such as the determination of pressure and temperature in the bearing surfaces and the transition areas between journal and thrust bearing parts. Finally, the temperature distribution between a pure radial load on a journal bearing and a combined load on the identical journal-thrust bearing will be compared using the example of an operating point.

This master´s thesis solves the problem of stationary viscous flow of incompressible fluids in thin layers of fluid film lubrication in fixed pad thrust bearings. The parametric computational model of oil domain was created for investigation the distribution of pressure, velocity and thermal fields together with the determination of the basic parameters as axial force, heating up and friction loss. Subsequently this model was applied for investigation influence of uneven bearing clearance. The problem task was solved by final volume method in Ansys CFX 12.0 software.

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Die elektromagnetische Dynamik von axialen Magnetlagern ist im besonderen Maße von den eingesetzten Materialien abhängig. Axiale Flussverläufe machen eine Blechung von Stator und Rotor unwirksam und hohe induzierte Spannungen rufen im Magnetkreis wirbelstrombedingte Gegenfelder hervor. Zusätzliche kompensierende Magnetisierungsströme lassen den messbaren Strom der Steuerspule dem kraftbildenden Hauptfluss vorauseilen. Steigende Anforderungen an die Regeldynamik erfordern daher den Einsatz schwach elektrisch leitfähiger Kernmaterialien (Soft Magnetic Composites) oder eine Berücksichtigung der auftretenden Wirbelstromeffekte in der Regelstrecke unter Anwendung von Systemen gebrochenrationaler Ordnung. Beide Optionen werden in diesem Beitrag aus analytischer Sicht gegenübergestellt und ihre Anwendungsfälle diskutiert.