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ECOLE DOCTORALE SI-MMEA (http://simmea.ed.univ-poitiers.fr/)
2015 Doctoral research projects for PhD recruitment
I- General information :
VILLE, LABORATOIRE
Town, Laboratory
Etablissement
Institution
TITRE en français
French title
TITRE en anglais
English title
Directeur(s) de thèse (HDR)
Supervisor(s)
Taux d’encadrement prévu (%)
Supervising rates (%)
Co-encadrant(s)
Co-supervisor(s)
Taux d’encadrement prévu (%)
Supervising rates (%)
Contact pour informations
Contact for information
Compétences requises
Pre requisite
Poitiers (FR) :
P’D1*
P’D2*
P’D3*
Limoges (FR) :
SPCTS*
GEMH*
La Rochelle (FR) :
LaSIE*
UP*
ENSMA*
UL*
ENSCI*
ULR*
ANALYSE EXPERIMENTALE DU COMPORTEMENT NON-LINEAIRE
DES ROTORS SUPPORTES PAR DES PALIERS ET DES BUTEES
AERODYNAMIQUES
EXPERIMENTAL ANALYSIS OF NON-LINEAR ROTORS SUPPORTED BY
AERODYNAMIC JOURNAL AND THRUST BEARINGS
Nom 1 : Arghir
Prénom 1 : Mihai
% : 50
Nom 2 :
Prénom 2 :
%:
Nom 1 :
Nom 2 :
Julian
Prénom 1 : LeRouzic HDR ?
50% :
Prénom 2 :
HDR ?
oui X non
oui
non
%:
Nom : Arghir
Prénom : Mihai
Tel : 05.49.49.65.40
Email : mihai.arghir@univ-poitiers.fr
Vibrations, Dynamique non-linéaire, Génie Mécanique
Vibrations, Nonlinear Dynamics, Mechanical Design
*Sigle : P’D1, P’D2 et P’D3 : Départements D1, D2 et D3 de l’institut P’ : http://www.pprime.fr/;
SPCTS : http://www.unilim.fr/spcts/; GEMH : http://www.avrul.fr/spip.php?rubrique39; LaSIE :
http://www.univ-larochelle.fr/LaSIE,
UP
http://www.univ-poitiers.fr/,
ENSMA
http://www.ensma.fr/, UL : http://www.unilim.fr/, ENSCI : http://www.ensci.fr/, ULR :
http://www.univ-larochelle.fr/.
II- Description of the 3 year doctoral research project
(please make a complete description of the doctoral research project. Do not forget to mention
when the contract will start and to give an estimation of the net salary per month)
Aerodynamic journal and thrust bearings represent a technology for guiding low power rotating
machinery (less than 400 kW) but operating at very high speeds (beyond 30 krpm). This technology
is considered as being “clean” because it replace the usual lubricant (oil for example) with air or with
a working gas. The advantages are not only ecological but the design of the rotating machine is also
improved and simplified because a lubrication system and seals are not necessary anymore. These
considerable advantage brought this technology under the focus of the aerospace industry that is now
looking for simple and reliable solutions for replacing the ball bearings operating in a cryogenic
environment.
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Research activities on this topic are developed since 2005. They enabled the continuous
developement of these technology from both theoretical and experimental standpoints: original
theoretical models for journal bearings were developed and two rotordynamic test rigs were build. A
first test rig is dedicated to the analysis of an horizontal rotor supported on aerostatic hybrid
journalbearings and/or aerodynamic foil journal bearings. The second test rig consists of a vertical
rotor suported by ball beraings mounted with a dead band clearance and by aerostatic bearings of
Lomakin type. Both test rigs are entrained by air driven, Pelton turbines.
Work to be performed:
 New aerodynamic foil bearings will be designed and will need intensive testing on the rig using
an horizontal rotor. The goal of the tests will be the measurement of the start-up torque, of the top
speed and the appropriate description of the non-linear dynamic response of the rigid rotor guided
by these bearings. The data acquisition and parameter identification methods used up to now will
need to be consolidated. The second step of the experimental activity will be the analysis of the
response of a flexible rotor suported on foil journal bearings. Up to now only rigid rotors were
tested and the behavior of flexible rotors is not much documented in the literature. It is also a
demand of the industry that must be dealt with great care and free of any commitement.
 The test rig using a vertical flexible rotor showed a very complex non-linear responses. The
origins of these non-linearities are the dead band clearance of the ball bearings and the internal
damping of the rotor stemming from its complex design. Up to now only the first aspect was
analyzed and taken into account in simulations. The goal of the work will be the combined
analysis of both aspects (dead band clearance of the ball bearings and internal damping) by using
a commercial rotordynamic code and confronting experimental findings with theoretical results.