HDR defense : Kerem EGE

Abstract :

The objective of this Habilitation to Supervise Research is to synthesize my research work and the scientific
research work and the scientific issues that I have developed during my academic career, from those
academic career, from those that emerged during my master's research internship at ENSTA (IMSIA) and then
during my doctoral thesis at the LMS (X) to my recent academic and industrial projects at the
Acoustic Vibrations Laboratory (LVA) where I was recruited in 2010. After a presentation of my
presentation, the presentation will focus on the presentation of my research activities which are based on the
of modelling and dynamic characterisation of complex structures over a wide frequency band with a particular
The first part, "experimental", will be based on a study of the dynamics of the structure.
The first part, "experimental", will be devoted to my main research theme
which concerns the characterisation of complex, anisotropic structures in the various frequency domains of
of interest for industrial vibro-acoustic problems. The central idea of my
experimental work since my PhD thesis until today has consisted jointly in extending the "modelling" approaches
modal" approaches (the high resolution time domain methods and the ESPRIT method in particular) and
ESPRIT method in particular) and to extend the propagative approaches (wave number identification) to low frequencies.
(identification of wave numbers) by adapting them to complex (possibly anisotropic) systems of
anisotropic) systems of interest. The accurate identification of broadband damping is the most critical point and requires
and requires adaptability and constant effort by necessarily coupling the different modal and propagative
and propagative approaches over different, partially overlapping frequency domains. Some
concrete applications in vibro-acoustics of the high resolution modal analysis method (HRMA)
method I have developed will be detailed, followed by the major advances obtained on the techniques
identification of wave numbers and material properties will be presented: Hankel function correlation method
correlation method for isotropic and orthotropic elliptical structures, anisotropic RIC method for
anisotropic RIC method for force identification and characterisation (Fabien Marchetti's thesis), and
HRWA method (2D-ESPRIT) for wave number identification (Pierre Margerit's thesis).
Laminated sandwich structures will be used as a case study for the application of the different experimental techniques
techniques, with particular attention to verifying the comparison and overlap of the methodologies
superposition of the methodologies despite the different underlying theoretical formulations.
In the second part "modelling" I will synthesise my different contributions and my
In the second part, "modelling", I will synthesise my various contributions to the development of equivalent models in broadband vibro-acoustics.
The focus will be on stiffened orthotropic plane structures with application to the vibroacoustics of
the piano soundboard (a periodically stiffened complex spruce structure). Two models
will be detailed: a synthetic description based on a small number of parameters called
descriptors and an equivalent simplified analytical model of stiffened structures of any shape
(Benjamin Trévisan's thesis). Then I will present the major axis of my current theoretical research which deals with the equivalent
which deals with the equivalent modelling of multilayer structures (composites, anisotropic)
in a wide frequency band. Based on this formalism an equivalent dynamic model of
anisotropic multilayer materials has been developed (Fabien Marchetti's thesis). Two scientific
Two scientific locks have been lifted: to extend to anisotropy (any orientation angles of the layers)
the thin plate equivalent approach and unify the definitions of dynamic damping in the literature by correcting the one implicit in the
literature by correcting the one implicit in the thin plate equivalent model.
The HDR defence will conclude with a presentation of my short and medium term research project, the collaborations and theses recently started, the perspectives for the development of my research themes and the new scientific questions envisaged.

Rapporteurs :
Alain BERRY, Professeur, Université de Sherbrooke
François GAUTIER, Professeur, Le Mans Université
Morvan OUISSE, Professeur, ENSMM

Jury :
Jérôme ANTONI, Professeur, INSA Lyon, Examinateur
Alain BERRY, Professeur, Université de Sherbrooke, Rapporteur
François GAUTIER, Professeur, Le Mans Université, Rapporteur
Éric JACQUELIN, Professeur, Université Claude Bernard Lyon 1, Examinateur
Morvan OUISSE, Professeur, ENSMM, Rapporteur
Émeline SADOULET-REBOUL, Maître de Conférences, UFC, Examinatrice

Invité : Fabien CHEVILLOTTE, Ingénieur de Recherche, MATELYS Research Lab