Keywords: scientific visualization, sound intensity, acoustic mapping.

Much of the theoretical research concerned with acoustics provides useful information about pressure fields, but none currently offers a full mapping of the acoustic energy flow (vectorial effects) in the front and back of any scattering systems working in three-dimensional real environmental conditions. Interference, diffraction and scattering of waves made the real field very complex and difficult compared with the theoretical modelling. This is one of the reasons why the experimental investigations of acoustic fields using sound intensity (SI) techniques are such effective and serviceable methods. Besides that, sound intensity investigation techniques are very useful in locating noise sources and provide the advantage that the measurements can be made in almost any environment without the requirement of special facilities such as an anechoic room, and the research can be made in the presence of parasitic noise: a very important attribute in industry vibroacoustic investigations.

The visualization of acoustic energy flow in real-life acoustic three-dimensional space fields can explain many particular energetic effects (perturbations and vortex flow, effects of scattering in the direct and near field, etc.), concerning the areas in which it is difficult to make numerical modelling and analysis with the numerical simulation methods. The sound intensity image represents a more accurate and efficient information compare to the spatial pressure acoustic fields modelled.

The article presents the application of a SI technique to graphically present a spatial distribution the acoustic energy flow over the barriers of various geometrical shaped structures located in a three-dimensional space. As the results of research, the graphic analysis of the sound intensity flux in two and three-dimensional space is show. Visualisation of the research results is shown in the form of intensity streamlines in space and as the shape of a flow wave or an isosurface in three-dimensional space. Numerous examples illustrate the application of the SI measurement for practical problems for vibroacoustical diagnostic and noise abatement.

Our experiments confirm that flow acoustic imaginations in real-live conditions are very complex, even for extremely simple modelling facility used in this study. These investigations provide a physical understanding of acoustic wave flow phenomena in real conditions where the measurements show both qualitative and quantitative flow diagnostics. The presentation of the vector distributions of real-live acoustic fields in the areas for which it is difficult to make a theoretical analysis (direct field and near field), can explain many particulars concerning the radiation character of surface sources, and the scattering of waves around obstacles. Further research will focus on the importance of these interaction phenomena for more realistic engineering applications.

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