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At least 1,315 records · Page 73

Dynamic behavior of air lubricated pivoted-pad journal-bearing, rotor system. 2: Pivot consideration and pad mass

Rotor bearing dynamic tests were conducted with tilting-pad journal bearings having three different pad masses and two different pivot geometries. The rotor was vertically mounted and supported by two three-pad tilting-pad gas journal bearings and a simple externally pressurized thrust bearing. The bearing pads were 5.1 cm (2.02 in.) in diameter and 2.8 cm (1.5 in.) long. The length to diameter ratio was 0.75. One pad was mounted on a flexible diaphragm. The bearing supply pressure ranged from 0 to 690 kilonewtons per square meter (0 to 100 psig), and speeds ranged to 38,500 rpm. Heavy mass pad tilting-pad assemblies produced three rotor-bearing resonances above the first two rotor critical speeds. Lower supply pressure eliminated the resonances. The resonances were oriented primarily in the direction normal to the diaphragm.

Nemeth, Z. N.↗

Experiments on the stability of various water-lubricated fixed geometry hydrodynamic journal bearings at zero load

Hydrodynamic journal bearing stability tests were conducted with 1.5 in. diameter, 1.5 in. long fixed geometry bearings in water at 80 F with zero load. Five fixed geometry bearings were rated in order of diminishing stability as follows: (1) three-tilted-lobe bearing (offset factor of 1.0), (2) herringbone-groove bearing, (3) one-segment, three-pod, shrouded Rayleigh-step bearing, (4) three-tilted-lobe journal with axial grooves (offset factor of 1.0) mated with a plain bearing, and (5) three-centrally-lobed bearing with axial grooves (offset factor of 0.5). The various parameters that affect the stability of each bearing configuration were investigated.

Schuller, F. T.↗