References of "Bozet, Jean-Luc"
     in
Bookmark and Share    
Peer Reviewed
See detailTribologie en oxygène liquide
Bozet, Jean-Luc ULg; Bozet, Jean-Luc ULg; Gras, R. et al

in Matériaux et techniques ”, SIRPE, numéro hors série, 38èmes Journées du cercle d’études des métaux (1999, December)

Detailed reference viewed: 53 (4 ULg)
Peer Reviewed
See detailThe optical EHD method applied to the study of ageing of biodegradable oils
Cloesen, C.; Kabuya, A.; Bozet, Jean-Luc ULg

in Journal of Synthetic Lubrication (1998), 15(1), 1-12

In the present study, modifications of the lubricating properties of vegetable oils, which had undergone accelerated ageing, were quantified, using the optical EHD method. Each oil sample was examined in ... [more ▼]

In the present study, modifications of the lubricating properties of vegetable oils, which had undergone accelerated ageing, were quantified, using the optical EHD method. Each oil sample was examined in an optical viscometer in order to measure film thickness vs. contact speed. From these results the pressure—viscosity coefficient was calculated, by adjusting theoretical values. The modifications were related to molecular changes, which were observed with various tools of chemical analysis, including gel permeation chromatography (GPC). [less ▲]

Detailed reference viewed: 3 (0 ULg)
Peer Reviewed
See detailApplication de la méthode EHD à l’étude du vieillissement d’huiles biodégradables
Cloesen, C.; Kabuya, A.; Bozet, Jean-Luc ULg

in Synthetic Lubrication (1998, April), 15(1), 3-12

Detailed reference viewed: 16 (0 ULg)
Peer Reviewed
See detailDesign of an axial mechanical gas seal with self-acting lift geometry
DOCQUIER, N.; NELIS, M.; Bozet, Jean-Luc ULg

in European Journal of Mechanical and Environmental Engineering [=EJMEE] (1998), 43(no4), 195-203

Cet article étudie le comportement d'un joint mécanique sans contact à faces radiales, doté d'un dispositif d'augmentation de portance. La répartition des pressions et des vitesses dans le film mince est ... [more ▼]

Cet article étudie le comportement d'un joint mécanique sans contact à faces radiales, doté d'un dispositif d'augmentation de portance. La répartition des pressions et des vitesses dans le film mince est établie grâce à l'équation de Reynolds résolue au moyen de différences finies. L'étude paramétrique des caractéristiques du joint est ensuite réalisée en vue d'en déduire des abaques de fonctionnement et, par la suite, une démarche cohérente de choix des dimensions. L'auteur présente donc tout d'abord le fonctionnement d'un joint mécanique à gaz et il en décrit la géométrie et les conditions de travail. Après avoir défini et justifié les hypothèses utilisées, il propose une mise en équation du problème et décrit le comportement du système d'étanchéité en régime au moyen des résultats obtenus. L'article présente finalement l'influence de la géométrie du joint et propose une méthode de dimensionnement. [less ▲]

Detailed reference viewed: 14 (0 ULg)
Full Text
Peer Reviewed
See detailThe Tribology of Valve Seals in Cryogenic Rocket Engines
de Lamotte, E.; Bozet, Jean-Luc ULg; Garcia Marirrodriga, C.

in 7th European Space Mechanisms and Tribology Symposium (1998)

Detailed reference viewed: 25 (5 ULg)
Full Text
Peer Reviewed
See detailNanoindentation and scanning force microscopy as a novel method for the characterization of tribological transfer films
Randall, N. X.; Bozet, Jean-Luc ULg

in Wear (1997), 212(1), 18-24

In conventional pin-on-disk testing of the tribological characteristics of two different materials in sliding contact, the main parameters of interest are notably the friction and wear properties of the ... [more ▼]

In conventional pin-on-disk testing of the tribological characteristics of two different materials in sliding contact, the main parameters of interest are notably the friction and wear properties of the material pair. However, when two bodies consisting of hard and soft materials respectively are subjected to such testing, the appearance of a transfer film, or third body, which can be a composite mixture of the two, is often observed. Until now the characterization of transfer films in terms of their mechanical properties has been hampered by their nonhomogeneous distribution across a tested surface, their small size, low thickness and the difficulty in accurately positioning a test probe such that the film properties can be measured independently from those of the substrate. In this paper a new method is introduced, consisting of nanoindentation and scanning force microscopy (SFM), which is capable of highly localized indentation testing of a specified sample site with high resolution imaging of the area prior to and after indentation. In this way the hardness and modulus of a transfer film can be obtained, as well as valuable surface topographical information concerning the material response to the indentation. Measurements are presented for the material pair A286/polyimide after testing on a pin-on-disk tribometer in ambient air and liquid nitrogen. Distinct variations in hardness between the transfer films and their contacting bodies have een observed and correlated to the wear behaviour and testing environment. (C) 1997 Elsevier Science S.A. [less ▲]

Detailed reference viewed: 25 (1 ULg)
See detailNouvelle approche du calcul des roulements à billes non lubrifiés
Bozet, Jean-Luc ULg

Doctoral thesis (1996)

Detailed reference viewed: 37 (6 ULg)
See detailTribology in Aerospace Propulsion Mechanisms
Bozet, Jean-Luc ULg

in Space Scientific Research in Belgium, vol. IV : Space Technology (1996), 4

Detailed reference viewed: 12 (2 ULg)
See detailThe Assessment of vegetable oils as renewable environmentally acceptable lubricants
CLOESEN, C.; NELIS, M.; KABUYA, A. et al

Scientific conference (1996)

Detailed reference viewed: 10 (1 ULg)
Peer Reviewed
See detailComparative analysis of the lubricating power between a pure mineral oil and biodegradable oils of the same mean iso grade
Kabuya, A.; Bozet, Jean-Luc ULg

in Dowson, D.; Taylor, C. M.; Childs, T. H. C. (Eds.) et al Lubricants and lubrication : proceedings of the 21th Leeds-Lyon symposium on tribology held at the Institute of Tribology , University of Leeds U.K., 6th-9th September 1994 (1995)

n this paper, we compare the viscosimetric and tribological properties of some vegetable oils and one synthetic ester with a pure mineral oil. The viscosimetric characteristics of lubricants show that ... [more ▼]

n this paper, we compare the viscosimetric and tribological properties of some vegetable oils and one synthetic ester with a pure mineral oil. The viscosimetric characteristics of lubricants show that both vegetable oils and ester have a higher viscosity index than mineral oil. The test results show that all tested oils have a somewhat dilatant behaviour.The oiliness, antiwear and extreme pressure properties of lubricants have been studied respectively with a Stribeck machine and a four-ball machine. We have noted the following: On the four-ball machine, extreme pressure results expressed in terms of pressure wear index and mean hertz load show that the higher performance is obtained with the vegetable oils. Extreme pressure results expressed in terms of weld load, do not show a big difference between the tested oils. Antiwear results expressed in terms of wear scar show that die highest performances are obtained with vegetable oils. On the Stribeck machine, oiliness results expressed in terms of friction coefficient indicate that: in the regime of fluid lubrication, tested oils have me same behaviour; in die boundary lubrication regime, both vegetable oils and synthetic, ester have a better response uian mineral oil. [less ▲]

Detailed reference viewed: 37 (2 ULg)
Peer Reviewed
See detailCaractérisation du frottement sous forte accélération et forte charge
husque, J.-P.; Bozet, Jean-Luc ULg; al

in Actes des Journees internationales francophones de la Societe Tribologique de France (1995), 1

Detailed reference viewed: 19 (1 ULg)
Peer Reviewed
See detailInfluences physico-chimiques sur le comportement tribologique des résines polyimides
LE MOIGNE-QUILLIEN, M.; Bozet, Jean-Luc ULg

in Matériaux et Techniques (1995), (n° 5-6,), 43-48

Physical and chemical properties vary with temperature. In a sliding contact between a pair of materials, high speeds can provoke a rise of the temperature of these materials due to the heat produced by ... [more ▼]

Physical and chemical properties vary with temperature. In a sliding contact between a pair of materials, high speeds can provoke a rise of the temperature of these materials due to the heat produced by friction. Consequently, the increase of temperature can modify physical and chemical properties affecting their tribological behaviour. Tribological tests performed on polyimide resins sliding against austenitic stainless steel indicate that there is a friction transition which is temperature dependent. A wear transition accompanying the friction transition was not observed. The tests were performed during a research campaign developed in order to investigate the behaviour of some pairs of materials which can be used in a tightness or a bearing function for valves in aerospace applications. [less ▲]

Detailed reference viewed: 15 (0 ULg)
Peer Reviewed
See detailDéveloppement d'un boîtier d'essai dédié à l'expérimentation d'un roulement à billes noyé dans l'oxygène liquide
Bozet, Jean-Luc ULg; Germain, Albert ULg; JUERY, B.

in Mécanique Industrielle et Matériaux (1994, December), 47(5), 463-467

Les roulements à billes de la turbopompe alimentant un moteur fusée cryotechnique en oxygène liquide sont des organes mécaniques dont la définition est délicate. Pour le compte de l'Agence Spatiale ... [more ▼]

Les roulements à billes de la turbopompe alimentant un moteur fusée cryotechnique en oxygène liquide sont des organes mécaniques dont la définition est délicate. Pour le compte de l'Agence Spatiale Européenne (E.S.A.), sous la responsabilité de la Société Européenne de Propulsion (S.E.P.) et la maîtrise d'œuvre du Centre National d'Etudes Spatiales (C.N.ES.-France), un programme de caractérisation expérimentale du fonctionnement de ces roulements a conduit une association de plusieurs laboratoires de l'Université de Liège à réaliser un banc d'essai spécifique. Grâce à la pneumatique, le concept mécanique retenu permet de solliciter le roulement à éprouver par des charges radiales et/ou axiales variables en cours d'essai. Ce concept mécanique, la nature et la régulation des fluides nécessaires au bon fonctionnement du banc, la conduite informatique d'un essai ainsi que la mesure des paramètres physiques utiles à la quantification des performances du roulement noyé dans l'oxygène liquide font l'objet de développements ci-après. Parmi ces paramètres physiques, on dénombre la température de la bague intérieure du roulement. Cette température s'avère décisive pour détecter rapidement les signes précurseurs de la dégradation du roulement soumis à des conditions précises de charges, de débit d'oxygène liquide sous pression et de vitesse de rotation. [less ▲]

Detailed reference viewed: 28 (2 ULg)
See detailAnalyse surfométrique de phénomènes tribologiques : dégradation des surfaces fonctionnelles
Bozet, Jean-Luc ULg; NELIS, M.

Scientific conference (1994, November)

Detailed reference viewed: 11 (0 ULg)
Peer Reviewed
See detailLa tribologie, une spécialité liégeoise
Bozet, Jean-Luc ULg

in Athena (1994), 97

Detailed reference viewed: 20 (5 ULg)
Peer Reviewed
See detailThe regularity of the friction coefficient : different means of characterization
Bozet, Jean-Luc ULg; NELIS, M.

in Proc. 6th International Congress on Tribology (1994), 5

Detailed reference viewed: 8 (0 ULg)
Peer Reviewed
See detailNumerical solutions on non steady-state conditions of lubrication in internal combustion engine bearing
NELIS, M.; Bozet, Jean-Luc ULg

in Proc. 6th International Congress on Tribology (1994), 4

Detailed reference viewed: 7 (0 ULg)