POST-DOC POSITION on Acoustics Gallery Waves

MISE EN LIGNE : | DATE DE CLÔTURE : Indéfinie Recrutement Offre d'emploi temporaire (CDD) et stages Doctorat Niveaux Localisation Nantes

Fiche de poste

  • Organisation: Geophysics and Non Destructive Laboratory, Ifsttar, France (www.ifsttar.fr)
  • Location: Nantes, France
  • Research Field: Acoustics, Waves
  • Type of contract: Temporary
  • Duration: 12 months    
  • Job Status: Full-time
  • Application deadline: The position is immediately available.

Contactodile.abraham(at)ifsttar.fr and fabien.treyssede(at)ifsttar.fr

Your tasks

We are looking for a highly motivated post-doc to take up a research position on the modelling of ultrasonic gallery waves in a sphere embedded in a solid. You will work on a project funded by the Region Pays de la Loire (France) whose aim is to develop new concept of sensors to recover the stress tensor inside solid.

Your first goal will be to demonstrate that gallery waves exist in an elastic sphere (solid or hollow) embedded in an unbounded solid medium. The work will be performed on the theoretical and numerical side with the objective to understand the physics that governs the existence of such waves in this context.

The second objective will be to find the best way to generate (in space, time and polarisation) that kind of waves. Wave focalisation on a sphere circumference will be an underlying objective.

The third expected result is to find a robust observable(s) extracted from gallery waves propagation that is characteristic of the sphere radius. This last step will be completed by a   sensitivity analysis of this(ese) observable(s) to a radius modification.

To perform this work, the first step will be to carry an extensive bibliographic review and to theoretically study the governing equations of elastic guided wave propagation in a spherical coordinate system. The second step will consist in the development and implementation of a specific semi-analytical finite element (SAFE) method to solve the guided modes of the problem, following the same approach as for plates [Treyssède and Laguerre, J. Acoust. Soc. Am. 133 (6), 3827-3837, 2013]. With this kind of method, only the radial coordinate will have to be discretized with finite elements, which will lead to fast and accurate computations. The numerical development will be validated for configurations in-vacuo by comparison with literature results. Then, the spherical SAFE method will be combined with perfectly matched layers in order to account for the unbounded nature of the surrounding medium [Treyssède et al., Wave Motion 51 (7), 1093-1107, 2014]. The third step will aim to simulate spheres embedded into a solid medium in order to achieve the goals of the project (as defined above). The programming environment will be Matlab and the spherical SAFE method will be implemented in an in-house finite element code dedicated to waveguides and developed at the GeoEND laboratory.

You will be expected to publish scholarly papers and attend an international conference.

Your profile

You must hold a PhD in Acoustics or related to the physics/mathematics of waves.

Moreover, experience on the following will be highly beneficial :

  • guided waves
  • numerical modelling
  • finite element

Knowledge of English (oral and written) is mandatory and knowledge of French would be an advantage.

Application procedure

Please submit your application by email (titled : SMOG - Post-Doc application - Your Name) to odile.abraham(at)ifsttar.fr and fabien.treyssede(at)ifsttar.fr including a letter of motivation, CV, a list of publications and names and addresses of two academic references.

Any other way of applying will not be considered.

Include in your email :

  • Name
  • Citizenship
  • Date of Birth
  • Gender
  • Email
  • Skype
  • Motivation: provide up to three factual (if possible quantitative) arguments that demonstrate your academic excellence as researcher
  • Number of journal publications and DOI
  • CV
  • Motivation letter
  • Supporting documents (e.g. paper, list of publications, awards)