Skip to Main content Skip to Navigation
Theses

Non-elliptical point contacts : The Torus-on-Plane conjunction

Abstract : This thesis is dedicated to the study of torus on plane contacts under various operating conditions. They can be found at the interface between the torus roller-end and the flange in roller bearings. The first challenge of this thesis is to deal with unusual mating geometries. The other challenge is the presence of a complex kinematic which operates in these contacts. In order to further develop the understanding of such a contact, a dual approach (experimental and numerical) is adopted. The Jérotrib test-rig enables a first study, by considering that the élastohydrodynamic torus on plane contact can be modelled by an elliptical equivalent contact. Thanks to a differential colorimetric interferometry method which was improved and adapted during the thesis, precise film thickness measurements are carried out under a rather wide range of operating conditions. A thermo-elastohydrodynamic numerical model is developed and validated by comparing its results to the ones of the test-rig. A numerical study on film forming is then proposed and the role of the contact ellipticity is investigated. The numerical model is improved in order to take into account the actual shape of the solids. A film thickness validation of the model is proposed, thanks to measurements performed on the Tribogyr test-rig. The operating conditions are very similar to the one encountered in actual bearings, and the mating solids have representative geometries: it is an actual torus-on-plane contact. It is demonstrated that the lubricant shearing is responsible for the solids temperature rise, which in its turn, reduces the film thickness. It appears mandatory to be able to predict this global warming of the bodies. It is also demonstrated that the pressure and film thickness distributions lose their symmetry because of the spinning kinematic and the solids shape. However, the behaviour of the torus-on-plane contact appears very similar to the one of an elliptical equivalent contact, apart from some limit cases.
Complete list of metadatas

https://tel.archives-ouvertes.fr/tel-01791538
Contributor : Abes Star :  Contact
Submitted on : Monday, May 14, 2018 - 4:48:07 PM
Last modification on : Wednesday, July 8, 2020 - 12:42:36 PM
Long-term archiving on: : Tuesday, September 25, 2018 - 4:51:14 AM

File

these.pdf
Version validated by the jury (STAR)

Identifiers

  • HAL Id : tel-01791538, version 1

Citation

Jean-David Wheeler. Non-elliptical point contacts : The Torus-on-Plane conjunction. Mechanics [physics.med-ph]. Université de Lyon, 2016. English. ⟨NNT : 2016LYSEI131⟩. ⟨tel-01791538⟩

Share

Metrics

Record views

135

Files downloads

590