An Acoustics Intensity Based Investigation of the Energy Flow Over the Barriers |
| S. Weyna
West Pomeranian University of Technology, Poland |
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| Many of theoretical research of the acoustics fields provides useful information about pressure fields, but none currently offers a full mapping of the acoustic energy flow (vectorial effects) in front and back of any scattering systems working in 3D real environmental conditions. Interference, diffraction and scattering of waves made the real field very complex and difficult to the theoretical modelling. This is one of the reasons why the experimental investigations of acoustic fields using sound intensity (SI) technique are so effective and serviceable methods. The visualization of acoustic energy flow in real life acoustic 3D space fields can explain many particulars energetic effects (perturbations and vortex flow, effects of scattering in direct and near field, etc.), concerning the areas in which it is difficult to make numerical modeling and analysis with the CFD FSI CAA simulation methods. The sound intensity image represents a more accurate and efficient information compare to the spatial sound fields modelled. The article presents the application of SI technique to graphic presentation of spatial distribution the acoustic energy flow over the barriers of various geometrical shapes structures located in a three dimensional space. As the results of research, the graphic analysis of the sound intensity flux in 2D and 3D space is show. Visualisation of research results is shown in the form: of intensity streamlines in space and as a shape of flow wave or isosurface in three dimensional space. Numerous examples illustrate the application of the SI measurement for practical problems at the vibroacoustical diagnostic and noise abatement, as well as to the validation of results of CFD/CAA numerical modelling. The differences, if appearance, mainly result from the fact that theoretical forecasting uses far too big simplifications or that it is impossible to obtain proper data on real physical features of the tested area and structures. |
| DOI: 10.12693/APhysPolA.118.172 PACS numbers: |