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B. Scheichl:
"Feasibility study of a novel hydrodynamically lubricated thrust bearing device operated with water or saturated water vapour";
Report for Andritz AG, Mechanical Pulping Systems, Eibesbrunnergasse 20, A-1120 Vienna, Austria; Report No. 1, 2009; 14 pages.

A feasibility study concerning the stationary operation mode of a novel thrust bearing device, to be used in pulping systems, is presented. In essence, it consists of a circular stator, centrically parallel to the axisymmetric rotor, such that the tilting of the clearance between these two discs controls the hydromechanical operation of the bearing. Unlike the commonly adopted tilted-pads bearings, here the specific gap geometry is achieved by milling an annulus consisting of adjacent identical sectors from the surface of the stator, such that the tilting of the clearance in circumferential direction accounts for the hydrodynamical bearing behaviour. The maximum load-bearing capacity is found by optimising the azimuthal pitch. The lubricant is supplied radially at the inner edge of the annulus. As a consequence of the imposed supply pressure, the bearing operates in both hydrostatic and hydrodynamic mode, i.e. in hybrid mode, associated with the flow in radial and azimuthal direction, respectively. Both the cases water and saturated water vapour used as lubricants are investigated. In order to predict the hydromechanical performance, the basic equations of lubrication theory are solved by
adopting both analytical and numerical methods.