Researcher (M/F, fixed-term contract) on: Experimental study of the integration of non-linear energy sinks on an immersed hull model for very low-frequency vibration control

Job Description

Missions

The researcher will operate in the frame of the ANR Astrid project LoCNES (“Low frequency vibration control using non-linear energy sinks”).

Activity

He or she will join a project team formed by the IEMN, the LMA (Marseille), and NG (Naval Group), as part of an ANR Astrid project (funding specifically for dual-use research) that began in January 2026. The overall objective of the project is to demonstrate the potential of Non-linear Energy Sinks (NES) for controlling the very-low-frequency acoustic radiation of vessels. Indeed, at low frequencies, acoustic radiation can be significant, have a strong impact on the environment or on acoustic stealth, and is difficult to limit using conventional methods. While NES have already proven effective in attenuating vibration fields in air, specific challenges arise when transitioning to a heavy fluid environment, necessitating experimental validation of the models. This requires specific experimental facilities, in particular a large size acoustic water tank as the IEMN one (dimensions: 8x7 m2, 6 m deep).
In this context, the postdoctoral fellow will participate in the design and construction of a watertight, submersible cylindrical hull model (approximately one meter in size), based on rolled stainless steel metal sheet, as well as the support structures necessary for its installation in the IEMN acoustic test tank. Its design will be based on the findings from previous phases of the project, which involve equivalent measurements on a simpler system consisting of a plate on the water's surface. The postdoctoral researcher will also work on installing sensors inside the model (accelerometers, in particular), as well as a vibration source and the NES designed by the LMA. To better characterize the resulting vibration field, laser vibrometry measurements will be taken from the air and/or directly underwater.

Your Profil

Skills

The researcher must hold a Ph.D. in engineering, acoustics and vibrations, physics, or mechanics. Experience in the design, implementation, and use of characterization equipment (particularly laser vibrometer) or physical testing benches is strongly recommended, as are skills in managing physical measurement systems. The successful candidate is also expected to apply, in collaboration with the project team, their analytical and synthesis skills to manage all experimental data and use the results to present their work at conferences and in scientific articles.

Your Work Environment

The Institute of Electronics, Microelectronics and Nanotechnologies (UMR CNRS 8520 – https://www.iemn.fr/en/) is situated in Villeneuve D'Ascq, close to the city of Lille (France). With a staff of more that 500 persons, the institute's large field of research ranges from physics to material science, acoustics, micro and nanotechnologies. The Acoustics laboratory, workplace of the recruited researcher, is located in the center of Lille (41 Boulevard Vauban), in the “Junia” facilities.

Constraints and risks

Due to the potential defense applications of this study, applications will only be accepted after being validated by the French Agence Innovation Defense.

Compensation and benefits

Compensation

From €3,072 gross per month, depending on experience

Annual leave and RTT

44 jours

Remote Working practice and compensation

Pratique et indemnisation du TT

Transport

Prise en charge à 75% du coût et forfait mobilité durable jusqu’à 300€

About the offer

About the CNRS

The CNRS is a major player in fundamental research on a global scale. The CNRS is the only French organization active in all scientific fields. Its unique position as a multi-specialist allows it to bring together different disciplines to address the most important challenges of the contemporary world, in connection with the actors of change.

CNRS

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