On the Aerodynamic-Noise Sources in a Circular Cylinder Coated with Porous Materials

Research output: Chapter in Book/Conference proceedings/Edited volumeConference contributionScientificpeer-review

2 Citations (Scopus)
148 Downloads (Pure)


Coating a circular cylinder with porous materials constitutes an effective passive strategy for reducing the flow-induced noise linked to the vortex shedding. Despite the number of investigations in the last decade, the noise-mitigation mechanisms associated with this technique remain unclear. The present research aims to clarify the role played by the alterations in the flow field due to porosity in the aerodynamic-sound attenuation of a cylinder coated with metal foam. Far-field acoustic and particle-image-velocimetry (PIV) measurements were performed at the Delft University of Technology for Reynolds numbers ranging in the subcritical regime. The aeroacoustic results show that a significant tonal and broadband suppression could be achieved with the porous treatment of the body. For the coated cylinder, the dominant sources do not appear to be distributed over the surface but rather are situated several diameters downstream of it, with a lower amplitude. The PIV data reveal that the main effect of the coating is to stabilize the cylinder wake, which results in an elongation of the vortex-formation length and a decrease in the turbulence kinetic energy. In particular, the position where the vortex shedding starts corresponds to the region of the dominant noise sources. The conclusions drawn in this study potentially provide an insightful indication for the design of more effective sound-control solutions.
Original languageEnglish
Title of host publication28th AIAA/CEAS Aeroacoustics 2022 Conference
Number of pages14
ISBN (Electronic)978-1-62410-664-4
Publication statusPublished - 2022
Event28th AIAA/CEAS Aeroacoustics 2022 Conference - Southampton, United Kingdom
Duration: 14 Jun 202217 Jun 2022
Conference number: 28

Publication series

Name28th AIAA/CEAS Aeroacoustics Conference, 2022


Conference28th AIAA/CEAS Aeroacoustics 2022 Conference
Country/TerritoryUnited Kingdom

Cite this