Reduction of acoustic and aerodynamic noise through sustainable micro-pore absorbers

Land transport and aeronautical industries are currently faced with the challenge of the design of lightweight and compact acoustic materials capable of reducing under flow the low and medium frequency components (< 1 kHz) of surrounding noise sources. Current treatments for reducing internal and external noise are based on the use of acoustic resonators and porous materials whose effectiveness covers the medium and high frequency ranges. The search for passive acoustic treatments with low embarked mass and capable of reducing low frequencies remains an open problem. The general objective of the i-LINK+ Programme funded by the Spanish National Research Council (CSIC) is to stimulate the collaboration between national research groups and international research groups of the highest relevance in these fields. The domains of expertise for the LMA partner (Laboratory of Mechanics and Acoustics, France) are vibro-acoustics, fluid-structure coupling, and sound field synthesis. From the side of the ITEFI (Spain), they are experts in the active control of noise and vibration, the design and optimisation of micro-perforated insulating partitions, the wave propagation in metaporous media and the development of novel experimental methods in acoustics. Taking advance of the complementary capacities of both institutions, the objective of this collaboration project is to develop an innovative experimental methodology for the characterization of the acoustic attenuation properties of test materials in a test bench (without flow) and in a subsonic wind tunnel (under turbulent boundary layer). Non-intrusive measurements will be performed by Laser Doppler Velocimetry (VLD) to estimate the attenuation of acoustic pressure and velocity near test materials. They will be compared with measurements by nosecones microphones, hot-wire anemometry and pressure-velocity probes in order to define the field of application of the VLD method. Additional information may be obtained by Particle Imaging Velocimetry on the modification by the material of the structures present in the turbulent boundary layer.

 

 

Congresos y reuniones, conferencias
2023
GAA WIND TUNNEL TESTING OF MICRO-PERFORATED MATERIALS
Conferencia invitada

C. Maury and T. Bravo

Forum Acusticum 2023

Del 11 al 15 de septiembre de 2023, Torino, Italy.

GAA Causal-based optimization of micro-perforated treatments
Conferencia invitada

Maury, Cedric; Bravo, Teresa

Internoise 2023

Del 20 al 23 de agosto de 2023, Chiba, Japan.

GAA Modelling and characterization of micro-porous resonating liners under a low speed flow
Conferencia invitada

Cédric Maury, Teresa Bravo and Daniel Mazzoni

Flinovia IV Flow-Induced Noise and Vibration Issues and Aspects

Del 22 al 24 de mayo de 2023, Sydney, Australia.

2022
GAA In-situ measurements of the absorption properties of anisotropic fibrous materials: effects of porous shielding and fibers diameter
Conferencia invitada

T. Bravo and C. Maury

24th International Congress on Acoustics

Del 24 al 28 de octubre de 2022, Gyeongju, South Korea

GAA Enhanced micro-perforated wall-treatments for reducing the boundary layer noise in a low-speed wind-tunnel: modelling, characterization and optimization studies
Conferencia invitada

C. Maury and T. Bravo

Internoise 2022

Del 21 al 24 de agosto de 2022, Glasgow, UK.

GAA Causal-based Optimization of Micro-Perforated Partitions
Conferencia invitada

C. Maury and T. Bravo

16ème Congrès Français d’Acoustique

Del 11 al 15 de abril de 2022, Marseille, France.