Showing papers on "Fluid bearing published in 1991"
Book•
01 Jan 1991TL;DR: In this paper, the authors propose a simplified solution for deformation in dry contacts in Elastohydrodynamic Lubrication of Rectangular Conjunctions and a solution for elasthydrodynamic lubrication in ellipitcal conjunctions.
Abstract: 1: Introduction 2: Bearing Classification and Selection 3: Surface Topography 4: Lubricant Properties 5: Bearing Materials 6: Viscous Flow 7: Reynolds Equation 8: Hydrodynamic Thrust Bearings - Analytical Solutions 9: Hydrodynamic Thrust Bearings - Numerical Solutions 10: Hydrodynamic Journal Bearings - Analytical Solutions 11: Dynamically Loaded Journal Bearings 12: Hydrodynamic Journal Bearings - Numerical Solutions 13: Hydrodynamic Squeeze Film Bearings 14: Hydrostatic Lubrication 15: Hydrodynamic Bearings - Considering Fluid Inertia 16: Gas-Lubricated Thrust Bearings 17: Gas-Lubricated Journal Bearings 18: Hydrodynamic Lubrication of Nonconformal Surfaces 19: Simplified Solutions for Stresses and Deformations 20: General Solution for Stresses and Deformations in Dry Contacts 21: Elastohydrodynamic Lubrication of Rectangular Conjunctions 22: Elastohydrodynamic Lubrication of Ellipitcal Conjunctions 23: Film Thicknesses for Different Regimes of Fluid Film Lubrication 24: Rolling-Element Bearings 25: Additional Elastohydrodynamic Lubrication Applications 26: Non-Newtonian Fluid Effects in Elastohydrodynamic Lubrication 27: Thermo Elastohydrodynamic Lubrication.
1,688 citations
TL;DR: In this article, a powder lubricant consisting of a fine powder unserted either deliberately or one generated by the water of the mating surfaces, constitutes a viable lubricant that generates the required flows and pressures to prevent contact between the surfaces.
Abstract: This paper conceptualizes a powder lubrication mechanisms which closely resembles that of a hydrodynamic fluid film. Based on the observations of past investigations and on the author's experiments, it is postulated that a layered shearing of the compacted powder generates velocity, density, and temperature profiles akin to fluid film bearings. Thus, a lubricant consisting of a fine powder unserted either deliberately or one generated by the water of the mating surfaces, constitutes a viable lubricant that generates the required flows and pressures to prevent contact between the surfaces.
81 citations
TL;DR: In this paper, a modified Reynolds' equation is used to predict bearing behavior, patching together the different core formation cases, depending on the possible local formation of a rigid core which may be attached to either surface, or float between the surfaces.
Abstract: When the shear stress magnitude of a Bingham material exceeds the yield shear stress, quasi‐Newtonian flow results, otherwise the material is rigid. The Bingham model has been used in tribology to describe the behavior of greases, but may also be used for electrorheological fluids proposed as ‘‘smart’’ lubricants. For two‐dimensional flow, different modified Reynolds’ equations are obtained, depending on the possible local formation of a rigid core which may be attached to either surface, or float between the surfaces. From the modified Reynolds’ equation it is straightforward to predict bearing behavior, patching together the different core formation cases. Results are presented for two geometries: the squeeze film damper and the journal bearing.
74 citations
TL;DR: In this article, the problem of hydrodynamic lubrication under conditions of suddenly applied loads is investigated and a theory is developed and compared to known exact solutions in the simple squeeze-film case.
Abstract: The problem of hydrodynamic lubrication under conditions of suddenly applied loads is of practical importance and theoretical interest. For example, such conditions may occur if a turbine blade fractures. From a theoretical point of view, the classical theory of Reynolds, which is quasi-steady, may not be applicable. Reynolds' equation does not depend on bearing surface accelerations, which may be considerable, but only on bearing surfaces1 velocities. A theory is developed and compared to known exact solutions in the simple squeeze-film case. The theory is then applied to the case of a massive rotor simply supported by a short bearing, to which a large impulsive load is applied about the steady condition. Rotor trajectories are computed and in many instances a large difference is observed between the behavior predicted by the Reynolds equation and the improved theory. Results show that fluid inertia, not included in Reynolds' theory, has the desirable effect of suppressing the trajectory amplitude due to...
45 citations
TL;DR: In this paper, the characteristics of noncircular bearings, considering the effects of turbulence and cavitation, are numerically analyzed, and four bearing profiles are considered: circular, worn-circular, two-lobe and elliptical.
Abstract: In this paper, the characteristics of noncircular bearings, considering the effects of turbulence and cavitation, are numerically analyzed. Four bearing profiles are considered: circular, worn-circular, two-lobe and elliptical. To model the turbulence, the linearized lubrication theory of Ng and Pan is used. Reynolds' equation is suitably modified to account for both turbulence and cavitation. The equation is incorporated into the Elrod cavitation algorithm. This numerical procedure, which conserves mass throughout the bearing, implicitly incorporates the JFO boundary conditions at rupture and reformation boundaries. JFO theory is considered to accurately model cavitation in moderately to heavily loaded bearings. Performance predictions are compared to results presented in a variety of earlier papers. Presented at the 45th Annual Meeting in Denver, Colorado May 7–10, 1990
33 citations
Patent•
29 Nov 1991TL;DR: In this article, a hydrodynamic bearing is used as a radial or a thrust bearing in a spindle motor for a hard disk driver for a single-input single-out (SISO) hard disk drive.
Abstract: A ceramic hydrodynamic bearing used as a radial or a thrust bearing in a spindle motor for a hard disk driver. The bearing includes a ceramic bearing base having hydrodynamic pressure generating grooves. A sliding surface of the bearing base is irradiated with an energy beam with a high energy density to remove said material, thereby forming hydrodynamic pressure generating groove, and at the same time the grooves are coated with a modification layer that is formed by melting the ceramic material that constitutes said ceramic bearing base with the energy beam and by solidifying said ceramic bearing base.
18 citations
TL;DR: In this paper, a gas bearing with a bi-directional hydrodynamic geometry is presented and analyzed, where the configuration considered is an equally spaced set of alternating land and radial groove sectors, together forming a bearing surface.
Abstract: A gas bearing with a bi-directional hydrodynamic geometry is presented and analyzed. The configuration considered is an equally spaced set of alternating land and radial groove sectors, together forming a bearing surface. The typical operating gap of the bearing is very small and a predominant laminar viscous flow field is assumed. The Reynolds equation is therefore used to describe the flow field. A parametric study of the controlling equations shows that four dimensionless geometric parameters in conjunction with the bearing number fully define the problem. A simplified one-dimensional and a more complete two-dimensional steady-state analyses are performed to optimize the governing parameters for maximum load carrying capacity and maximum film stiffness. This study shows that the performance prediction capability of the one-dimensional model is overly conservative and not satisfactory, but that its parametric optima are in favorable agreement with the two-dimensional analysis results. The load carrying ...
16 citations
Patent•
28 Oct 1991
TL;DR: A screw compressor, having a housing with an inlet and an outlet opening in which two or more rotors are rotatably mounted on bearings as mentioned in this paper, is a type of fluid bearing that operates tightly in conjunction with a closely fitted cylindrical part of the housing.
Abstract: A screw compressor, having a housing with an inlet and an outlet opening in which two or more rotors are rotatably mounted on bearings. The bearings are equipped with helically meshing profiles which operate tightly in conjunction with a closely fitted cylindrical part of the housing. The bearing devices or the rotors consist at least in part of fluid bearings.
12 citations
Patent•
01 Apr 1991TL;DR: In this paper, a dynamic tester for testing vibration damping seals and bearings is constructed, with a hollow shaft extending through the seal or bearing, with the shaft internally supported at each end by fluid bearings on hollow bosses connected to an interior of an enclosure, with no rolling members connected to the shaft.
Abstract: A dynamic tester for testing vibration damping seals and bearings is constructed having a hollow shaft extending through the seal or bearing, with the shaft internally supported at each end by fluid bearings on hollow bosses connected to an interior of an enclosure, with no rolling members connected to the shaft is described. A high pressure working fluid is forced through the hollow bosses to operate the bearings. Additionally, the shaft is provided with a reaction turbine that angularly vents a portion of the high pressure working fluid in order to rotate the shaft at high speed, up to 40,000 rpm. The seal or bearing is mounted in a bushing, in turn supported by rods to a shaking device that vibrates the seal or bearing as the shaft is rotated. A plurality of proximity sensors are mounted from outside the enclosure to sense shaft and seal bushing vibrations, and a plurality of pressure ports are disposed in the enclosure to allow sensing of dynamic and static pressures of the testing apparatus.
12 citations
11 citations
TL;DR: In this paper, the results from experimental studies and computer simulation of hydro-dynamic tilting thrust bearings are presented, and the bearing performance in terms of outlet film thickness, friction coefficient, and bearing temperature was measured in a high speed thrust bearing test rig.
Abstract: In this paper results from experimental studies and computer simulation of hydro-dynamic tilting thrust bearings are presented. The bearing performance in terms of outlet film thickness, friction coefficient, and bearing temperature was measured in a high speed thrust bearing test rig. The numerical simulation involves the solution of the generalized Reynolds equation and the energy equation, which considers thermal effects on the oil viscosity and the squeezing of the oil film.
IBM1
TL;DR: Two-dimensional computations of the compressible Navier-Stokes equations are used to study the flow at the inlet and outlet of slider air-bearings operating under conditions typical of computer disk-storage devices.
Abstract: Two-dimensional computations of the compressible Navier-Stokes equations are used to study the flow at the inlet and outlet of slider air-bearings operating under conditions typical of computer disk-storage devices
08 Dec 1991
TL;DR: The results show that the hydrodynamic bearing effect, especially the squeeze effect, is significant for ultrasonic frequency contact of the rotor and stator.
Abstract: A hybrid numerical analysis that includes the hydrodynamic bearing effect and elastic contact in a ring-type ultrasonic motor is presented. The two-dimensional Reynolds equation is solved numerically by a finite difference algorithm. The rotor deformation is described by a one-dimensional Green's function obtained by using a finite element elastic analysis code. The contact problem is solved by an iteration method so that the contact condition and the hydrodynamic bearing condition are satisfied simultaneously. The results show that the hydrodynamic bearing effect is significant for ultrasonic frequency contact of the rotor and stator. Surface roughness, contact area, and normal vibrating speed of the stator are important parameters in the hydrodynamic bearing. >
TL;DR: In this paper, the effects arising from the variation of viscosity with hydrodynamic pressure and temperature have been incorporated in the analysis, and the resulting governing equations have been transformed to a set of ordinary differential equations which have been solved numerically using the Adams-Moulton method.
Patent•
25 Oct 1991TL;DR: In this article, a low pressure air bearing and rolling flexure bearing support for relative movement of carriage actuators in a disk drive system is presented, where air is channeled in small orifices formed into bearing pads to provide air pressure on both sides of planar carriages.
Abstract: A low pressure air bearing and rolling flexure bearing support for relative movement of carriage actuators in a disk drive system. Air generated by the disk rotation or by a simple blower mounted on the spindle is directed through conduits in the carriage support system. The air is channeled in small orifices formed into bearing pads to provide air pressure on both sides of planar carriages. The bearing pads extend beyond the direction of travel of the carriages. By providing air pressure over relatively large areas of the carriages, low pressure air can be used, generated by the system itself. Rolling flexure bearings provide constraint tot he carriage orthogonal to that of the air bearing and to the direction of travel.
TL;DR: In this article, the characteristics of spiral grooved thrust air bearings, i.e., stiffness, load capacity, power loss and the fraction of critical damping, are analyzed.
Abstract: The characteristics of spiral grooved thrust air bearings, i. e., stiffness, load capacity, power loss and the fraction of critical damping, are analyzed. The finite element method and the computer simulation method are applied to obtain the numerical solution of the Reynolds equation. Based on the computed results, the effects of various specific design parameters of the bearing on the load-carrying performance and the damping characteristics are discussed. The principles for the optimization of the bearing design are proposed.
Patent•
05 Mar 1991
TL;DR: In this paper, the authors proposed a method to obtain a long-life magnetic fluid bearing device or a motor which is effective for high-speed high accuracy rotation and excellent in sealing ability by applying turbulence of a flow to a magnetic fluid seal film formed on an end ring or a rotary shaft.
Abstract: PURPOSE:To obtain a long-life magnetic fluid bearing device or a motor which is effective for high-speed high accuracy rotation and excellent in sealing ability by providing a means for applying turbulence of a flow to a magnetic fluid seal film formed on an end ring or a rotary shaft. CONSTITUTION:There are provided a non-magnetic housing 7, a magnetic fluid seal 3 having an end ring 6 coaxially disposed in the housing 7 and a bearing 2, and further there is provided a permeable rotary shaft 1 extended piercing the above member. The end ring 6, the magnetic fluid seal 3 and the bearing 2 spaced from the magnetic fluid seal 3 are arranged in order from the open side of the housing 7. A lubricating fluid 8 is sealed in the bearing portion to form a space S between the lubricating fluid liquid level and the magnetic fluid seal 3, and a means for applying turbulence of a flow to a magnetic fluid seal film formed by the magnetic fluid seal 3 and the rotary shaft 1 by rotation of the rotary shaft 1 is provided on the end ring or the rotary shaft 1.
Patent•
07 Jan 1991
TL;DR: In this article, a ring groove was proposed to prevent or suppress a lubricant from being dissipated from a bearing section even when it is used for long period, by forming a ring hole, connected to the shaft hole of a sleeve at the outer position than the spiral group of a thrust bearing, on the bearing surface of a member.
Abstract: PURPOSE:To prevent or suppress a lubricant from being dissipated from a bearing section even when it is used for long period, by forming a ring groove, connected to the shaft hole of a sleeve at the outer position than the spiral group of a thrust bearing, on the bearing surface of a thrust bearing member. CONSTITUTION:When a rotating drum 3 is started to rotate, a lubricant 7 is fed under pressure from a groove 503 toward the center of a group 502 by the action of a spiral group 502, and a dynamic pressure is produced between the bearing surface 501 of a thrust bearing 5A and the bearing surface 201 of a stationary shaft 2. By this dynamic pressure, the bearing member 5A is floated by approx. 2mum from the bearing surface 201, and the drum 3 can be rotated smoothly without making in contact with the stationary shaft 2. Next, when the drum 3 is stopped, the bearing member 5A, floating by the dynamic pressure effect of the lubricant 7, comes in contract with the bearing surface 201, and the lubricant 7 between the bearing surface 501 of the bearing member 5A and the bearing surface 201 of the stationary shaft 2 is moved through the upper end of a shaft hole 401 to a groove 503 due to capillarity and kept inside the groove 503.
Patent•
05 Jul 1991
TL;DR: In this article, the authors proposed to increase load capacity and bearing rigidity and prevent transmission of vibration by fixing a magnet to a width direction intermediate part on the lower surface of a moving table and a magnetic unit on the upper surface of the base so as to attract the moving table.
Abstract: PURPOSE:To increase load capacity and bearing rigidity and prevent transmission of vibration by fixing a magnet to a width direction intermediate part on the lower surface of a moving table and a magnetic unit to a width direction intermediate part on the upper surface of a base so as to attract the moving table. CONSTITUTION:A magnet 11 is fixed to a width direction intermediate part on the lower surface of a moving table 3, while a magnetic unit 12 is fixed to the upper surface of a base 1, and the intermediate part of the moving table 3 is pulled downward by attracting force between the magnet 11 and the magnetic unit 12. As a result, compressed air is jetted from horizontal direction restricting air bearings 5, 5, and even when stress in an inner direction is generated in the bearing surface 5a of the bearing 5, the table 3 is not curved. Accordingly, clearance dimension in each part holds a design value, consequently load capacity and bearing rigidity are kept high and vibration to a bearing part from a driving part is prevented. Further, since a clearance between floating air bearing surfaces 8a, 8a and the upper surface of each of guide rails 2, 2 is decreased with a pressure of compressed air increased by the above described attracting force, the bearing rigidity in the vertical direction of a bearing unit is increased.
Patent•
21 Jan 1991
TL;DR: In this paper, a special air bearing structure for each of an X-axis carriage, a Y-Z carriage and a probe arm was designed to prevent a probe shaft from rotating or deflecting at the time of movement by comprising a special bearing structure.
Abstract: PURPOSE: To prevent a probe shaft from rotating or deflecting at the time of movement by comprising a special air bearing structure for each of an X carriage, a YZ carriage and a probe arm. CONSTITUTION: An orthogonal coordinate measuring apparatus 10 has a T-shaped base 12 attached to an X-axis carriage with a vertical column assembly 14 supported which can be moved along a first horizontal orthogonal axis. Pressurized guide air bearings 76a, b are placed behind a guide rail, while guide bearings 78a, b are placed in front close to a rotating table 20. Widely separated support air bearings 48a, b are placed in front of the X-axis carriage 40, while closely separated support air bearings 46a, b are placed behind. The front support air bearings 48a, b and corresponding pressurized air bearings 64a, b are placed at a distance along an X-axis, so that they effectively suppress dynamic chipping load caused by acceleration of the X-carriage 40 in a direction of the X-axis. The rear support air bearings 46a, b and pressurized air bearings 66a, b are closely separated and placed, so that three-point suspension is approached, thereby minimizing influence of incorrectness in ways 32 to 38.
Patent•
24 Dec 1991
TL;DR: In this paper, a rotary shaft and the end part of a housing on one thrust side was used to improve rigidity at both high and low speed revolutions by provid ing a rotating shaft and a housing with porous pads communicating with an air supply path.
Abstract: PURPOSE:To improve rigidity at both high and low speed revolutions by provid ing a rotary shaft and the end part of a housing on one thrust side which com pose the first radial bearing face with a thrust plate having a flange to compose the second radial bearing face with another member at an its end, and both radial bearing faces with a gaseous bearing mechanism, respectively. CONSTITUTION:A thrust plate 3 having a cylindrical flange 4 is fixed to both the ends of a rotary shaft 2 passing through a housing 1. The housing 1 is provided with porous pads 5, 6, 7 communicating with an air supply path 10, and the first and second radial bearings is formed between the porous pads 5, 6 and the flange 4, the rotary shaft 2, and a thrust bearing is composed of the porous pad 7 and the thrust plate 3. Thus, air bearing effect is given to both parts in which expansion caused by centrifugal force increases or decreases clearance between them, and the air bearings can therefore be given importance in their rigidity at high and low speed revolutions to steadily maintain the rigidity at the same level.
TL;DR: In this paper, a new type of modified energy equation including turbulence and surface roughness effects was derived and an adiabatic approximate solution for the static and dynamic characteristics of an 180°partial journal bearing with homogeneous surfaces roughness was presented.
Abstract: This paper describes the derivation of a new type of modified energy equation including turbulence and surface roughness effects and presents an adiabatic approximate solution for the static and dynamic characteristics of an 180°partial journal bearing with homogeneous surface roughness. Applying the modified turbulent lubrication equation and energy equation to the finite width partial journal bearings, the static and dynamic characteristics such as pressure and temperature distributions, load carrying capacity, friction coefficient, whirl onset velocity and so on are obtained numerically. In the numerical analysis of the modified energy equation, the adiabatic condition is assumed and then the heat transfer terms in the energy equation are omitted. The numerical results are indicated in graphic form for the various combinations of Reynolds number and relative roughness. Moreover, some numerical results of static characteristics are compared with the experimental results.
TL;DR: In this article, the authors deal with the problem of determing the influence of pressure at the bearing entry on load capacity and on the position of the resultant of the pressure forces in the case of a plane slider bearing.
Abstract: The present work deals with the problem of determing the influence of pressure at the bearing entry on load capacity and on the position of the resultant of the pressure forces in the case of a plane slider bearing; this work shows how a centrally pivoted pad may be employed where a shaft is also to be rotated in the reverse direction.
TL;DR: In this article, the authors solved the Reynolds' equation for the pressure distribution p(x,y) over a finite tiltedpad hydrodynamic bearing in terms of Bessel functions for the case where the clearance h(x) is of the form h0(R1/α−1)α (x/l)α, where h0 is the outlet clearance, R is the clearance ratio, α is a constant, x is a position coordinate along the pad and l is the pad's length.
Patent•
25 Jan 1991
TL;DR: In this paper, the authors proposed a method to accurately measure the thickness of a moving sheet material by providing rigid rings having air outlets on both sides of the sheet material to form an air bearing.
Abstract: PURPOSE: To accurately measure the thickness of a moving sheet material without damaging the sheet material by providing rigid rings having air outlets on both sides of the sheet material to form an air bearing. CONSTITUTION: Outside bearings 17a, 17b constituted of rigid rings each having a plurality of air outlets 18 provided to the periphery thereof are provided to the upper and lower gauge parts on both sides of a sheet 10 so as to leave an interval between the bearings. Further, disc-shaped inside bearings 23a, 23b are connected to the bearings 17a, 17b by elastic annular sheets 22a, 22b and each of them has a series of air outlets 24 provided to the periphery thereof. The annular sheets 22a, 22b are provided so that the bearings 23a, 23b are positioned on the almost same planes as the bearings 17a, 17b. The respective rings and bearings 23a, 23b of the bearings 17a, 17b form air bearings with respect to the sheet 10. By this constitution, air bearings can be effectively used with respect to a relatively thin moving paper sheet.
TL;DR: In this paper, a modified Reynolds equation combined with the modified Coyne-Elrod boundary conditions was used to calculate the film rupture location and the lubricant flow rate of a bearing.
Abstract: The load capacity, film rupture location and lubricant flow rate are computed using a modified Reynolds equation combined with the modified Coyne-Elrod boundary conditions. It was found that the pressure in the convergent portion of the bearing, and hence the load capacity, is increased significantly as the Reynolds number it increased. For small surface tension parameter, the load capacity is increased with increasing surface tension parameter, but is virtually independent of N* for N* > 2.5.
Patent•
04 Apr 1991TL;DR: In this article, a hydrodynamic bearing unit which supports a rotator on a fulcrum shaft at the fixed body side via a radial hydrogynamic bearing 12 and two thrust hydrodynamynamic bearings 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 34, 35, 36, 37, 38, 39, 38
Abstract: PURPOSE: To provide a hydrodynamic bearing unit that is capable of reducing the extent of torque at time of starting. CONSTITUTION: In a hydrodynamic bearing unit which supports a rotator on a fulcrum shaft at the fixed body side via a radial hydrodynamic bearing 12 and two thrust hydrodynamic bearings 13, 14, a support member 20 of this rotator is formed with a magnetic substance, while a magnet 26 attracting this support member is installed at the rotator side, and the support member 20 of the rotator is attracted by magnetic force of the magnet 26, through which dead load of the rotator to be added to the thrust hydrodynamic bearing 14 and another force are all offset or reduced. COPYRIGHT: (C)1992,JPO&Japio
Patent•
14 May 1991
TL;DR: In this article, a reaction force applying belt was applied to prevent the seizure between a rotary shaft and the bearing metal of a fluid bearing and drive the rotary motors in a stable state by axially supported by the fluid bearing.
Abstract: PURPOSE:To prevent the seizure between a rotary shaft and the bearing metal of a fluid bearing and drive the rotary shaft in a stable state by laying a reaction force applying belt onto the rotary shaft which is axially supported by the fluid bearing CONSTITUTION:A rotary shaft 1 is axially supported by a gas bearing 7, and an endless driving belt 5 is laid between a driving pulley 3 fitting-fixed on an electric motor shaft 11a and a following pulley 4 fitting-fixed on the rotary shaft 1 Further, a reaction force adjusting pulley 17 and two pulleys 23 are axially supported by a swing bearing 18 and bearings 24 and 24, respectively An endless belt 26 for applying reaction force is laid between the reaction force adjusting pulley 17 and the pulleys 24 and 24, and turned back to the electric motor 11 side from a part laid onto the pulleys 24 and 24, and laid onto the rotary shaft 1 By the reaction force applying belt 26, the tension force in the opposite direction to the tension force due to the driving belt 5 can be applied onto the rotary shaft 1, and the seizure between the rotary shaft 1 and a bearing metal is prevented, and a stable drive is permitted
TL;DR: In this paper, the effects of O-type cavitation on the static and dynamic characteristics of turbulent journal bearings submerged in the low viscosity lubricant are investigated theoretically, extending an idea of "general short bearing theory" proposed by Pan.
Abstract: In this research work, the effects of “O-type” cavitation on the static and dynamic characteristics of turbulent journal bearings submerged in the low viscosity lubricant are investigated theoretically. Extending an idea of “general short bearing theory” proposed by Pan to submerged turbulent journal bearings, “O-type” cavitation pattern, load carrying capacity and altitude angle are determined for a wide range of eccentricity ratio in both laminar and turbulent flow cases. In addition, under the assumption of small displacement of the journal center, the dynamic characteristics such as linearized spring and damping coefficients and whirl onset speed of rotor-bearing systems are obtained. Sample numerical results are indicated in graphic form and the relation between the “O-type” cavitation and the static and dynamic characteristics of submerged turbulent journal bearings is discussed. Presented at the 44th Annual Meeting in Atlanta, Georgia May 1–4, 1989