C. M. Taylor

An Experimental Study of Hydrodynamic Film Rupture in a Steadily-Loaded, Non-Conformal Contact

A study of ventilated gaseous cavitation in a steadily-loaded, non-conformal contact has been undertaken. The work is particularly appropriate to what can be called ‘lightly loaded’ situations such as those occurring in radial race seals and certain industrial coating processes. A wide-ranging experimental programme has been carried out and measurements of film rupture location and pressure distributions compared to computer predictions obtained using the cavitation boundary conditions of Coyne and Elrod. Photographic studies are also reported. The boundary conditions due to Coyne and Elrod have been confirmed as appropriate for the experimental conditions studied.

Film Rupture for a Lubricated Cylinder Lightly Loaded against a Plane

Two alternative approaches for considering gaseous cavitation in lightly loaded bearings are examined for the case of a lubricated cylinder sliding against a plane. Despite the disparate natures of the methods, it is shown that essentially similar design predictions are forthcoming. This, however, does not give an insight into the physical understanding of the situation.

Separation Cavitation; Solutions for the Infinite Width Cylinder-Plane and Journal-Bearing Configurations

Theoretical analysis of the infinite width cylinder-plane and journal-bearing configurations is undertaken using the separation cavitation boundary condition. The results could form the basis of ex...

A Determination of Cavitation Interfaces in Fluid Film Bearings Using Finite Element Analysis

The location of both rupture and reformation boundaries in liquid film bearings is important in determining overall performance characteristics. Finite difference approximations have been most widely used in the numerical analysis of hydrodynamic bearings, and the problem of determining cavitation interfaces may be trivial or extremely complex depending upon the physical model adopted. For some situations finite element analysis may offer an advantage and this possibility is investigated here.

An Analysis of the Circumferentially Grooved Journal Bearing with Consideration of Lubricant Film Reformation

An analysis of a central, circumferentially grooved journal bearing has been undertaken. As well as considering the rupture of the lubricant, detailed attention has been paid to film reformation. A computer program has been developed which automatically locates the cavitation region without manual intervention and the numerical analysis technique developed to do this is fully described. Results for the steady state and dynamic performance characteristics of the bearing are presented and predictions compared with other published work where possible. The effect of not considering the reformation of the lubricant film is examined and it is concluded that satisfactory predictions of performance can be obtained for all parameters except the axial flowrate.

A Theoretical Estimation of the Performance of Journal Bearings Operating in the Turbulent Lubrication Regime

The use of process fluids of low kinematic viscosity as lubricants and the ever increasing surface speeds which are being encountered in fluid-film bearings have meant an increase in the number of bearings which operate in the turbulent regime. This paper describes a theoretical evaluation of the performance of 360-degree journal bearings operating turbulently, presents generalized data and discusses the results with comments upon the assumptions made and practical realities.

Separation Cavitation in Lightly Loaded Fluid Film Bearings with Both Surfaces in Motion

For lightly loaded fluid film bearings in which gaseous cavitation occurs, application of the continuity boundary condition at the liquid-gas interface is not satisfactory. Two alternative boundary conditions have been postulated. The purpose of this paper is to examine the separation boundary condition; in particular, the effect of both bounding surfaces being in motion is studied. This situation might be used as a basis for experimental work designed to select the most appropriate boundary condition for lightly loaded bearings.In Part 2, the boundary condition is used to analyse the cylinder-plane and journal bearing configurations. The theoretical predictions for the operating parameters are examined to see if their magnitudes and/or trends could be used for comparing the available cavitation boundary conditions.

An Experimental and Theoretical study of Lubricant flow rate in Static, Grooved, Rectangular Thrust Bearings

The work to be described here was undertaken in the preliminary stages of a research programme designed to study the true extent of lubricant films in non-stationary, grooved, rectangular thrust bearings. In such externally pressurized bearings an air-lubricant interface may be formed. The study of this interface was seen as a useful step in a consideration of film formation and flow rate prediction in liquid film journal bearings.

Research Note: Film Rupture in a Dynamically-Loaded, Non-Conformal Contact

This note is concerned with the rupture of hydrodynamically lubricated films in infinitely-wide non-conformal contacts. An attempt to correlate previous experimental work with new analytical results using separation cavitation boundary conditions is reported. The correlation shows no overall improvement compared with that obtained using analytical results employing the more common Swift–Stieber boundary conditions. It is suggested that a more detailed examination of the physical processes at work when rupture occurs in dynamically-loaded thin-film contacts is needed.

Cage Slip in Roller Bearings

The occurrence of cage and roller slip in lubricated roller bearings has been observed under adverse conditions of high speed and low load. Whilst slip is not normally a problem in roller bearings, in certain applications, for example the bearings supporting gas-turbine shafts, it can pose difficult design problems. For such conditions, bearing distress may occur due to increased wear and heat generation. A reduction of slip may be effected by the use of out-of-round races causing a preloading of some of the rolling elements; this, however, entails a corresponding reduction in fatigue life.Work described in this paper supplements the small amount of existing experimental evidence available concerning slip in rolling-element bearings. As well as a consideration of the effects of load and speed on slip, particular attention is paid to the quantity of lubricant supplied and the degree of misalignment present and the influence of these parameters on slip. Experimental results show a considerable divergence fr...