Fluid flow and acoustic absorption in porous metallic structures using numerical simulation and experimentation
The need to cut down vibration and minimize back pressure wave in a loudspeaker has led to the choice of artificially-made metallic foam structure due to its important low weight, recyclable, stiffness, high surface area, and longer active product life for money. Commercially available highly porous...
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| Format: | Thesis (University of Nottingham only) |
| Language: | English |
| Published: |
2018
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| Online Access: | https://eprints.nottingham.ac.uk/53597/ |
| _version_ | 1848798962903941120 |
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| author | Otaru, Abdulrazak Jinadu |
| author_facet | Otaru, Abdulrazak Jinadu |
| author_sort | Otaru, Abdulrazak Jinadu |
| building | Nottingham Research Data Repository |
| collection | Online Access |
| description | The need to cut down vibration and minimize back pressure wave in a loudspeaker has led to the choice of artificially-made metallic foam structure due to its important low weight, recyclable, stiffness, high surface area, and longer active product life for money. Commercially available highly porous metallic structures are known to be poor sound absorber and there is a possibility that if they can be made by interacting with the shapes and structural properties of this material, they could make useful. Currently available poroacoustic models needed to describe the sound absorption behaviour of porous materials point out the permeability of this structure as the key parameter driving this behaviour. Knowing this parameter through experimentation or prediction is imperative to the design of material with novel attributes for this process.
Pore-level numerical simulation of fluid flow through low-density “bottleneck-type” structures using tomography images of the “real” structures and “unconventional” sphere-packing models have been used herein to account for this permeability with reasonable fit to experimental data of airflow measured across these structures. This parameter was observed to be dependent on the structural parameters of the porous medium and most importantly, its pore diameter openings. Theoretical models to account for flow behaviour of this structure at low and high fluid velocities were proposed. Optimal values of structural parameters needed for the design of “bottleneck-type” structure for efficient sound absorption were achieved for a hardbacked and airgap simulation. |
| first_indexed | 2025-11-14T20:28:07Z |
| format | Thesis (University of Nottingham only) |
| id | nottingham-53597 |
| institution | University of Nottingham Malaysia Campus |
| institution_category | Local University |
| language | English |
| last_indexed | 2025-11-14T20:28:07Z |
| publishDate | 2018 |
| recordtype | eprints |
| repository_type | Digital Repository |
| spelling | nottingham-535972025-02-28T14:13:37Z https://eprints.nottingham.ac.uk/53597/ Fluid flow and acoustic absorption in porous metallic structures using numerical simulation and experimentation Otaru, Abdulrazak Jinadu The need to cut down vibration and minimize back pressure wave in a loudspeaker has led to the choice of artificially-made metallic foam structure due to its important low weight, recyclable, stiffness, high surface area, and longer active product life for money. Commercially available highly porous metallic structures are known to be poor sound absorber and there is a possibility that if they can be made by interacting with the shapes and structural properties of this material, they could make useful. Currently available poroacoustic models needed to describe the sound absorption behaviour of porous materials point out the permeability of this structure as the key parameter driving this behaviour. Knowing this parameter through experimentation or prediction is imperative to the design of material with novel attributes for this process. Pore-level numerical simulation of fluid flow through low-density “bottleneck-type” structures using tomography images of the “real” structures and “unconventional” sphere-packing models have been used herein to account for this permeability with reasonable fit to experimental data of airflow measured across these structures. This parameter was observed to be dependent on the structural parameters of the porous medium and most importantly, its pore diameter openings. Theoretical models to account for flow behaviour of this structure at low and high fluid velocities were proposed. Optimal values of structural parameters needed for the design of “bottleneck-type” structure for efficient sound absorption were achieved for a hardbacked and airgap simulation. 2018-12-12 Thesis (University of Nottingham only) NonPeerReviewed application/pdf en arr https://eprints.nottingham.ac.uk/53597/1/MY%20THESIS%205%20FINAL%20Abdulrazak%20Otaru.pdf Otaru, Abdulrazak Jinadu (2018) Fluid flow and acoustic absorption in porous metallic structures using numerical simulation and experimentation. PhD thesis, University of Nottingham, United Kingdom. Absorption of sound; Porous materials; Aluminum foam |
| spellingShingle | Absorption of sound; Porous materials; Aluminum foam Otaru, Abdulrazak Jinadu Fluid flow and acoustic absorption in porous metallic structures using numerical simulation and experimentation |
| title | Fluid flow and acoustic absorption in porous metallic structures using numerical simulation and experimentation |
| title_full | Fluid flow and acoustic absorption in porous metallic structures using numerical simulation and experimentation |
| title_fullStr | Fluid flow and acoustic absorption in porous metallic structures using numerical simulation and experimentation |
| title_full_unstemmed | Fluid flow and acoustic absorption in porous metallic structures using numerical simulation and experimentation |
| title_short | Fluid flow and acoustic absorption in porous metallic structures using numerical simulation and experimentation |
| title_sort | fluid flow and acoustic absorption in porous metallic structures using numerical simulation and experimentation |
| topic | Absorption of sound; Porous materials; Aluminum foam |
| url | https://eprints.nottingham.ac.uk/53597/ |