Three-year PhD position on aeroacoustics black holes for the reduction of sound emissions and fine particles in the atmosphere: Numerical and experimental study (funded by Amidex)

RESEARCHER PROFILE: PhD / R1: First stage Researcher                 
RESEARCH FIELD(S)1: Engineering
MAIN SUB RESEARCH FIELD OR DISCIPLINES1: Acoustics, Fluid dynamics, Particle dynamics 

JOB /OFFER DESCRIPTION 
The goal of zero emissions in the transport and energy sectors is the key to achieving an urban environment that is more resilient to climate change and with a lower impact on the health of the population. This notably involves reducing two factors: noise emissions and the emissions of ultrafine particles into the atmosphere from vehicles and industrial infrastructures.

This dual objective is part of the multidisciplinary international research project AERMES: “Aero-acoustic metamaterials for the reduction of noise and aerosols in the atmosphere” (n° AMX-22-RE-AB-157) funded by the AMU A*MIDEX foundation, bringing together the Laboratory of Mechanics and Acoustics (LMA, France), the Spanish National Research Council (CSIC) and the Institute for Research on Non-Equilibrium Phenomena (IRPHE, France).

The objective of this PhD position is to simulate, optimize and characterize the performance of silencers such as aero-acoustic black holes (ABH) in order to effectively attenuate sound emissions while improving the agglomeration of fine particles into aerosols of larger size, readily filtered by traditional techniques. The idea is to exploit the effective slow-down of sound waves entering the ABH, in order to produce nucleation zones of the ultra-fine particles convected by the flow.

The study will be based on modeling (Finite Element Method, Lattice Boltzmann Method) and heuristic optimization methods to reveal the trapping and total dissipation of acoustic waves within ABH structures as well as fine particle agglomeration. The thesis tasks will be:

• to analyze under which conditions the ABH effect is robust to the presence of low Mach number flows.
• to understand the particle agglomeration mechanisms induced by the trapping and slow-down of acoustical waves.
• to optimize the geometric shape of the silencer to maximize the ABH effect and particle agglomeration while minimizing the pressure and viscous drags.
• to design and validate an eco-friendly ABH prototype experimentally validated on an aero-acoustic test bench.

Publications:

• Ng BF, Xiong JW, Wan MP (2017) Application of acoustic agglomeration to enhance air filtration efficiency in air-conditioning and mechanical ventilation (ACMV) systems. PLoS ONE12(6): e0178851. https://doi.org/10.1371/ journal.pone.0178851
• Deaconu M, Radulescu D, Vizitiu G (2018) Acoustic study of different mufflers based on metamaterials using the black hole principle for aircraft industry, In: Proceedings of Euronoise 2018, pp. 2271–2276, Heraklion, Greece.
• Bravo T, Maury C (2023) Broadband sound attenuation and absorption by duct silencers based on the acoustic black hole effect: Simulations and experiments. Journal of Sound and Vibration 561:117825. https://doi.org/10.1016/j.jsv.2023.117825
• Maury, C, Bravo, T (2023) Vibrational Effects on the Acoustic Performance of Multi-Layered Micro-Perforated Metamaterials. Vibration, 6, 695-712. https://doi.org/10.3390/vibration6030043
• Maury, C, Bravo T, Mazzoni D (2021) Absorption and transmission of boundary layer noise through micro-perforated structures: measurements and modellings. In: FLINOVIA - Flow-Induced Noise and Vibrations Issues and Aspects - III, pp. 227–258, Springer Nature, Switzerland. https://doi.org/10.1007/978-3-030-64807-7_11

TYPE OF CONTRACT: TEMPORARY / JOB STATUS: FULL TIME / HOURS PER WEEK:  35
APPLICATION DEADLINE: 30/04/2024 23:30
ENVISAGED STARTING DATE: 01/10/2024
ENVISAGED DURATION: 36 months
JOB NOT FUNDED THROUGH AN EU RESEARCH FRAMEWORK PROGRAMME
WORK LOCATION: Laboratory of Mechanics and Acoustics (LMA CNRS UMR 7031), 4 impasse Nikola Tesla, 13013 Marseille France

WHAT WE OFFER: 
Additional information: The Euraxess Center of Aix-Marseille Université informs foreign visiting professors, researchers, postdoc and PhD candidates about the administrative steps to be undertaken prior to arrival at AMU and the various practical formalities to be completed once in France: visas and entry requirements, insurance, help finding accommodation, support in opening a bank account, etc. More information on AMU EURAXESS Portal 

QUALIFICATIONS, REQUIRED RESEARCH FIELDS, REQUIRED EDUCATION LEVEL, PROFESSIONAL SKILLS, OTHER RESEARCH REQUIREMENTS 

• Holder of a MSc or Engineering degree
• Solid background in acoustics and fluid mechanics 
• Skills in computational modelling and experimental methods
• English: working proficiency
• Skills in scientific communication (publication writing)

Soft skills: Analytical and critical thinking, Co-operation, Teamwork, Autonomy

REQUESTED DOCUMENTS OF APPLICATION, ELIGIBILITY CRITERIA, SELECTION PROCESS
Please provide a CV, motivation letter, qualifications marks and letters of recommendation to the project scientific supervisors, Prof. Cédric Maury and Dr. Teresa Bravo (see “how to apply” website). Before ranking and selection, the eligible candidates will be interviewed by the supervisors. 

HOW TO APPLY
Prof. Cédric Maury: cedric.maury@centrale-marseille.fr

More info at: https://laboratoire-mecanique-acoustique.fr/theses-stages/1156-these-2024-aeroacoustic-black-holes-for-the-reduction-of-sound-emissions-and-…