6926475966

«•»

%

Key Words: Bearings, Stiffness coeff icients, Domping coeffi-cients

Th© performance of a helical-grooved floating-ring bearing operated in turbulent regime has been studied. The load capacity of this type of beering is proportional to the sum of speeds of journal and ring whereas the power loss is approxi-mately proportional to the difference of these speeds. Nu-merical resuits of dynamie stiffness and damping, thecritical mass plus the static performance are presented in graphical forms or tables to facilitate design of this type of bearing. Performance comparisons are mada with respect to those of a single journal bearing.

84-1674

An ExtemaIIy Presaurized Su personie Caa Thruat Bearing (2nd Report. Dynamie Characteriatica in Supersonic Operations and Statie Characteriatica in Sonie Operations)

V. Miyake. T. Inaba. and T. Matsuoka Osaka Univ., Suita, Osaka, 565 Jap an. J. Tribology. Trans. ASME, J06 (1). pp 169-173 (Jan 1984) 8 figs, 2 refs

Key Words: Bearings. Gas bearings, Cleerance effects, Damp-ing coefficrents. Stiffness coefficients

The dynamie characteristics of a newly proposed supersonic gas thrust bearing are analyzed under supersonic operations. tts static characteristics in sonie operations are also investi-gated. It is concluded that the load capacity, the stiffness factor, and the damping factor are jncreased proportionally to the supply pressure in either supersonic or sonie operation rangę which is determined according to the magnitude of the cleerance.

84-1676

The Role of Cavitation in Whirl Instability in a Rotor Bearing, 2 - Effect of Oil bilet Position and Supply Preaaure

J. Brindley, L. Elliott, and J.T. McKay

Univ. of Leeds, UK, ASME Paper No. 83-WA/APM-25

Key Words: Bearings. Whirling, Cavłty effect

Whirl orbits have been calculated for a cavitated rotor bearing in which the cavity is assumed to form at an oil inlet groove and occupy the region in which subambient pressure is predicted from the equations of motion. Variations in position of the inlet groove and in the oil supply pressure have a profound influence on the behavior of the journal, largely through the v8rietions in cavity site and position that are produced.

GEARS

(AIsoseeNo. 1565)

84-1677

Study on the Effect of Tooth Fatigue on Dynamie Performance of Ge ar Pair (lat Report: In the Caae of biduction-Hardened Chromium Molybdenum Steel Geara)

K. Fujita, A. Yoshida, S. Nakata, and K. Kominami Okayama Univ., Tsushima, Okayama City. 700 Japan, Buli. JSME._26J222). pp 2272-2278 (Dec 1983) 17 figs, 5 refs

Key Words: Geers. Gear teeth, Fatigue life, Fatigue tests

• V

£

T--

w &

84-1675

The Role of Cavitation in Whirl Instability in a Rotor Bearing, 1 - The 7r-Film Model

J. Brindley. L. Elliott. and J.T. McKay

Univ. of Leeds, UK, ASME Paper No. 83-WA/APM-24

Key Words: Bearings, Whirling

In order to elucidate the feilure moda. load carrying capacity and relation between tooth profile change and dynamie performance in fatigue process of a surface hardened gear, operational fatigue tests w era performed using induction-hardened chromium molybdenum steel gears. The failure modę in these experiments was prtting or tooth breakage dua to tooth surface fatigue except one exampJe in which tooth breakage occurred at tooth fillet. Tooth root strain, modę in tooth stress frequency distribution, noisa and vibration inereased as the tooth profile was degradad.

W

Dynamically łoaded rotor bearings are frequently observed to parform whirling motions, in which the center of the rotor describes some sort of closed orbit. In this paper it is demonstrated by using numerical computations of whirl orbits in a simple 7T-film model, the rola of cavitation of the lubricant in enabling fluid forces alone to drive such stable orbits for cartain ranges of parameter values.

84-1678

Gear Single Tooth Bending Fatigue Test

R.W. Buenneke, M.B. Siane, C.R. Dunham, M.P. Semenek. M.M. Shea, and J.E. Tripp

£•

64

$

Sa

a • •