https://cyberleninka.org/article/n/544115.pdf

Hydrodynamic lubrication of textured surfaces: A review of modeling techniques and key findings

The Stribeck curve plays an important role in identifying boundary, mixed, elastohydrodynamic, and hydrodynamic lubrication regimes. Recent advances in elastohydrodynamic lubrication together with rough surface interaction have made it possible to develop a methodology for predicting the trend of the Stribeck curve. In this paper; we report the results of a series of experiments performed on a journal bearing together with a theoretical prediction of the Stribeck-type behavior. Various loads and oil temperatures are considered. The comparison between the experimental results with a mixed elastohydrodynamic lubrication model for line contacts is indicative of good agreement.

The Stribeck Curve: Experimental Results and Theoretical Prediction

Lubrication mode analysis of articular cartilage using Stribeck surfaces.

Health condition monitoring for rotating machinery has been developed for many years due to its potential to reduce the cost of the maintenance operations and increase availability. Covering aspects include sensors, signal processing, health assessment and decision-making. This article focuses on prognostics based on physics-based models. While the majority of the research in health condition monitoring focuses on data-driven techniques, physics-based techniques are particularly important if accuracy is a critical factor and testing is restricted. Moreover, the benefits of both approaches can be combined when data-driven and physics-based techniques are integrated. This article reviews the concept of physics-based models for prognostics. An overview of common failure modes of rotating machinery is provided along with the most relevant degradation mechanisms. The models available to represent these degradation mechanisms and their application for prognostics are discussed. Models that have not been applied...

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A review of physics-based models in prognostics: Application to gears and bearings of rotating machinery:

Engineering practices and analyses have indicated that surface textures and topography may significantly affect the tribological performance of contact interfaces. Such an influence may be complicated and difficult to be captured with only a few statistic surface parameters. The need for further improvement of the performance and life of machine elements requires that surface topography and textures he optimized. The utilization of a numerical tool to determine the basic geometric aspects of surface textures may be named a virtual texturing technology, with which surface optimization may start from patterned surfaces where topography can be precisely quantified and the relationship between textures and lubrication performance can be numerically established. Presented in this paper are the concept of the virtual texturing technology, models involved, and a preliminary exploration of the relationship between a dimpled texture design and the mixed lubrication characteristics for a typical counterformal contact. The dimple influence area and the number of interruption are found to be two key factors for designing dimpled surfaces for counterformal contact lubrication. It is demonstrated that virtual texturing is able to provide comparative information and directions for innovative surface design and optimization.

Virtual Texturing: Modeling the Performance of Lubricated Contacts of Engineered Surfaces

A mixed-TEHD analysis and experiment of journal bearings under severe operating conditions

The Stribeck curve is an overall view of friction variation in the entire range of lubrication, including the hydrodynamic, mixed, and boundary lubrication This paper presents the results of research on the friction of a journal-bearing conformal contact system in the form of Stribeck curves through numerical simulation The surface roughness of the journal and the bearing and material elasticity and thermoelasticity are included in the modeling, and their influences on the results of Stribeck curves are discussed A three-dimensional Stribeck surface is constructed to illustrate the load effect on friction for the modeled journal-bearing structure Review led by Gary Barber

Development of a Set of Stribeck Curves for Conformal Contacts of Rough Surfaces

A mixed lubrication model is developed to investigate the lubrication of coupled journal-thrust-bearing systems The governing equations are mapped into a computational domain with a conformal mapping technique developed in a previous study by Wang et al (2002) In order to study the influence of the boundary conditions on the performance of the bearing system, either the Reynolds boundary conditions or the JFO's mass conserving conditions are applied to the governing Reynolds equations The performance of a typical coupled journal-thrust bearing system is numerically investigated and the effects of viscosity, misalignment angle and feeding scheme are discussed

Mixed Lubrication of Coupled Journal-Thrust-Bearing Systems Including Mass Conserving Cavitation

A mixed-EHL analysis of effects of misalignments and elastic deformations on the performance of a coupled journal-thrust bearing system

A finite element model is presented for mixed lubrication of journal-bearing systems operating in adverse conditions. The asperity effects on contact and lubrication at large eccentricity ratios are modelled. The elastic deformation due to both hydrodynamic and contact pressure, and the cavitation of the lubricant film are considered in the model system. Two verification problems with both theoretical and experimental comparisons are given to show the effectiveness of this model. Finally, a new example is presented which discusses the influence of waviness depth, secondary roughness, external force and shaft speed on the mixed lubrication. Copyright © 2004 John Wiley & Sons, Ltd.

Yansong Wang

Papers

A mixed-TEHD analysis and experiment of journal bearings under severe operating conditions

Development of a Set of Stribeck Curves for Conformal Contacts of Rough Surfaces

Mixed Lubrication of Coupled Journal-Thrust-Bearing Systems Including Mass Conserving Cavitation

A mixed-EHL analysis of effects of misalignments and elastic deformations on the performance of a coupled journal-thrust bearing system

Finite element method for mixed elastohydrodynamic lubrication of journal‐bearing systems