Towards a control of acoustic energy conversion in structured porous materials
Résumé
Manipulating porous material’s geometry allows the control of internal viscous and thermal processes.Generally, these processes are interconnected due to the material’s microstructure. For instance, simple geometries like uniform cross-section materials exhibit interrelated viscous and thermal reactions. By altering the pore size (i.e. the hydraulic radius), both thermal and viscous effects can be tuned. This applies to conventional acoustic materials such as fibers, open-cell foams, and granular materials. However, there are cases where independent management of thermal or viscous effects is crucial. In thermoacoustics, enhancing heat exchange while minimizing viscous losses is necessary. In acoustics,maximizing both effects is essential for dissipating acoustic energy. Nevertheless, there are situations,like low particle velocity scenarios (e.g., thin materials on rigid surfaces or in low-frequency cavities),where increasing viscous dissipation may not be impactful. For this reason maximizing the thermal power exchanged could improve acoustic absorption. In this work we will show some preliminary studies conducted on a particular geometry of porous material in which it is possible to control these two effects separately.
Domaines
Sciences de l'ingénieur [physics]
Origine : Fichiers produits par l'(les) auteur(s)