Effects of Two Film Rupture Models on the Thermal Analysis of a Journal Bearing

Knight, J. D.; Niewiarowski, Alexander

doi:10.1115/1.2920240

Cited by 21 publications

(5 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Such a situation is, of course, difficult to treat analytically. Knight and Niewiarowski (1990) also predicted the temperature profile for the above cases using a gas bubble model and obtained good agreement with the experimental data in the cavitated region. The gas bubble model assumes that the film is continuous in the cavitated region, but the effective density and viscosity of the film are varied according to the gas fraction.…”

Section: Numerical Examplessupporting

confidence: 57%

An Efficient Numerical Procedure for Thermohydrodynamic Analysis of Cavitating Bearings

Vijayaraghavan

1996

Journal of Tribology

View full text Add to dashboard Cite

In this paper, an efficient and accurate numerical procedure to determine the thermo-hydrodynamic performance of cavitating bearings is described. This procedure is based on the earlier development of Elrod for lubricating films, in which the properties across the film thickness are determined at Lobatto points and their distributions are expressed by collocated polynomials. The cavitated regions and their boundaries are rigorously treated. Thermal boundary conditions at the surfaces, including heat dissipation through the metal to the ambient, are incorporated. Numerical examples are presented comparing the predictions using this procedure with earlier theoretical predictions and experimental data. With a few points across the film thickness and across the journal and the bearing in the radial direction, the temperature profile is very well predicted.

show abstract

Section: Numerical Examplessupporting

confidence: 57%

An Efficient Numerical Procedure for Thermohydrodynamic Analysis of Cavitating Bearings

Vijayaraghavan

1996

Journal of Tribology

View full text Add to dashboard Cite

show abstract

“…ρ and μ in equations (1) and (2), are taken as being homogeneous and can be expressed as functions of the properties of the fluid and gas, and the fraction of each phase, which are further computed by the cavitation model described in the following. This approach was first proposed and proved to be effective by Knight and Niewiarowski 23 to the authors’ knowledge, and has then been used by various researchers. 7,24–28 Its advantage lies in that it avoids the unfeasible determination of the multiple free boundaries of striations and the mass continuity in all regions of the bearing can be easily ensured.…”

Section: Numerical Formulationsmentioning

confidence: 99%

Development and validation of a gaseous cavitation model for hydrodynamic lubrication

Song

Ren

2015

Proceedings of the Institution of Mechanical Engineers, Part J:

View full text Add to dashboard Cite

The prediction of cavitation in lubricants is of significance to the design and analysis of hydrodynamic bearings. In this paper, a numerical model for the gaseous cavitation in hydrodynamic lubrication problems is derived based on the cavitation mechanism and origination, which is different from the conventional cavitation conditions. The proposed gaseous cavitation model is then used to calculate the performance of several types of bearings, including a two-axially grooved plain journal bearing, a misaligned journal bearing and parallel thrust bearings with surface textures. The results are validated with experimental data and numerical results calculated by the Half-Sommerfeld, Reynolds, and JFO conditions. The advantage of this new model lies in its accuracy and its independence from the cavitation pressure, which is usually difficult to be accurately defined. Thus this gaseous cavitation model can be useful in the accurate prediction of the cavitation phenomenon and performance of hydrodynamic bearings under steady state.

show abstract

“…3 The mechanism of vapour cavitation [5] Fig. 4 Oil streamlets in the cavitated region of bearing [5] mixture of lubricant and vapor exists in the cavitated zone with a mean physical properties depending upon the fractions of liquid and vapour. The liquid fraction is computed on the basis of continuity requirements.…”

Section: First Modelmentioning

confidence: 99%

Thermohydrodynamic analysis of cavitating journal bearings using three different cavitation models

Nassab

Maneshian

2007

Proceedings of the Institution of Mechanical Engineers, Part J:

View full text Add to dashboard Cite

In this paper, a thermohydrodynamic (THD) analysis of vapour cavitation in steady loaded and finite length journal bearing has been developed using three different cavitation models. It involves the simultaneous solution of the three-dimensional Navier-Stokes and energy equations by CFD technique. An orthogonal grid is generated using analytic transformation functions and the governing equations are transformed for use in the computational plane. These equations are made discrete by means of control volume method and the well-known SIMPLE algorithm is used for the pressure-velocity calculation. In the cavitated part of the lubricant flow with a mixture of vapour and liquid, three different cavitation models are used to obtain the thermal behaviour of lubricant flow in this region. In all of the three cavitation models, an attempt is made to replace a single phase fluid with equivalent properties instead of the mixture of liquid and vapour. The calculated results are compared with the theoretical results of other investigators and also with experiment, and the abilities of the proposed cavitation models to predict THD characteristics of journal bearings are examined. The numerical results show that the third model in which the liquid fraction is calculated based on continuity requirement for three-dimensional cavitated flow, predicts well the lubricant pressure and temperature fields in journal bearings.can either be a result of: (1) dissolved gas coming out of the solution or (2) evaporation of the fluid. Both types of cavitation are commonly observed in journal bearings. The occurrence of cavitation in journal bearings is shown to result in reduced power loss, friction coefficient, bearing torque and load capacity [1].Computed performance characteristics of a journal bearing depend significantly on the cavitated model and the related boundary conditions used in the analysis. For the steadily loaded journal bearings under laminar flow and isothermal conditions, several boundary conditions in the cavitated region have been proposed, some of which are listed in a paper by Mori and Mori [2].A computational cavitation algorithm was introduced by Elrod [3] which can be used in liquidfilm lubrication problems with or without cavitation region. In that work, a single 'universal' differential equation for the whole lubrication region was derived JET238 Fig. 7 Bush inner surface temperature distribution of the Mistry's bearing c/r s = 0.004, Re = 7.2, ε = 0.15, L/D = 0.5 JET238

show abstract

Effects of Two Film Rupture Models on the Thermal Analysis of a Journal Bearing

Cited by 21 publications

References 0 publications

An Efficient Numerical Procedure for Thermohydrodynamic Analysis of Cavitating Bearings

An Efficient Numerical Procedure for Thermohydrodynamic Analysis of Cavitating Bearings

Development and validation of a gaseous cavitation model for hydrodynamic lubrication

Thermohydrodynamic analysis of cavitating journal bearings using three different cavitation models

Contact Info

Product

Resources

About