Intervenants

Benyebka BOU-SAID (INSA Lyon, Université de Lyon, LaMCoS)

Opening ceremony. Tribology: future trends and demand areas

Noël BRUNETIERE (CNRS, Université de Poitiers, P'Prime)

The mixed lubrication regime and the role of surface topography : application to seals

The operating principles and characteristics of seals will be recalled. Then the presentation will focus on the lubrication regime of the sealing interface which is generally the seat of a mixed regime where the load is supported both by the asperities in contact and the fluid to be sealed. The role of surface roughness on the sealing response and performance will be discussed on the basis of numerical simulations and test results.

Jean BOUYER (CNRS, Université de Poitiers, P'Prime)

Lubrication in rotating machinery : numerical and experimental aspects.

Part I : theoretical analysis and application to journal and thrust bearings. Principples of hydrodynamic lubircation, Reynolds equation with analytical resolution and application to simple cases. Thermo-Hyrdo-Dynamic lubrication and its implementation for numerical analyses. Introduction to TEHD lubrication.

Part II : Experimental aspects. Introduction to what is interresting to measure on journal and thrust bearings. Presentation on how to get those measurements with different types of sensors. Presentation of test rigs at Pprime institute and results obtained with discussion.

Martin DIENWIEBEL (Karlsruhe Institute of Technology)

Experimental Nano- and Microtribology

Identifying the governing mechanisms in applied tribological systems that are responsible for the friction and wear behavior is a difficult task. Often they are hidden on the micro- or molecular scale even when the system is macrosopic. In this course, I will first review important nanoscale phenomena and concepts. I will the focus on experimental strategies to perform microtribological experiment in controlled conditions and will then discuss analytical methods that can be used to obtain a deeper insight.

Nikolay GARABEDIAN (Karlsruhe Institute of Technology)

Tribodigitalization is a process that can be seen as a strategy for harnessing rich tribo-data sets with the aim of finding more efficient solutions for investigating friction and wear. The extreme diversity of tribological testing procedures makes it especially challenging to find a unified approach to the problem. In this lecture we will review the benefits of producing "good" data, explore where tribology stands in digitalization, and how each of us can start producing machine-learning-ready data.

Tarek MABROUKI (ENIT, Université de Tunis El Manar)

On the Critical Role of Tribology in Improving Machining Efficiency

This course explores the crucial role of tribology in machining processes, emphasizing the importance of considering friction, wear, and lubrication to enhance machining efficiency. The course covers the fundamental mechanisms of friction and wear, examines factors that directly influence cutting tool performance, and presents various characterization methods to evaluate friction and wear during machining. It also provides an in-depth examination of lubrication techniques, including the highly effective approach of minimum quantity lubrication, highlighting their substantial contribution to reducing friction and wear. The course also addresses surface integrity and finishing operations, with a focus on specific tribological considerations in different machining processes. Advanced topics include in-depth discussions on tribology in high-speed machining and post-treatment of materials in additive manufacturing. Additionally, methodologies for integrating tribological aspects into machining modeling and simulation will be presented.

Francesco MASSI (La Sapienza, Université de Rome)

Into the complexity of dry contacts, where no formalism is permitted.

Contact interfaces working in dry conditions are object of several theoretical, numerical and experimental investigations. Nevertheless, their constitutive characteristics, such as discontinuity, heterogeneity, evolutive morphology and composition, allow neither a formalism in their description nor predictive tools. A general description of contacts by the conceptual tool of the tribological triplet will be followed by a description of the main wear and damage phenomena, considering some design guidelines. A specific focus will be addressed as well to friction-induced vibrations, rising thanks to the quota part of energy which is not directly dissipated within the interface, but is reinjected in the system under the form of acoustic energy. 

Guillermo MORALES ESPEJEL (SKF, INSA Lyon)

Rolling bearing lubrication and life models

Contents: Elastohydrodynamic lubrication (EHL) applied to rolling bearings,  EHL solution models, roughness effects in lubrication, ISO failure modes in rolling bearings.

Rolling bearing life concepts, ISO 281 Life models. Models for surface failures in rolling bearings. Incorporation of surface failure modes on bearing life calculation. Generalization to gears.

Michael MOSELER (Université de Fribourg)

Multiscale modeling of lubricants

The Reynolds lubrication equation (RLE) is widely employed to design sliding contacts in mechanical machinery. In order to predict friction in the hydrodynamic lubrication regime, the RLE requires accurate constitutive laws for pressure-dependent density and viscosity. This lecture explains how such laws can be extracted from classical molecular dynamics simulations. It also demonstrates, that an additional non-linear wall-slip law relating wall slip velocities to local shear stresses extends the RLE’s validity range to the mixed and boundary lubrication regime.