Comparison of 2D and 3D scanning solutions for sound visualization

The efficient identification of the areas that produce significant acoustic excitation is one of the main challenges of most noise and vibration problems. The introduction of novel scanning techniques such as Scan & Paint enables to acquire an extensive amount of information in a fast and efficient manner whilst preserving the simplicity of a single probe solution. Acoustic variations throughout space can be determined by combining the signals acquired with tracking information. The direct visualization of the resulting sound pressure, acoustic particle velocity or sound intensity fields can be achieved in a matter of minutes, obtaining a detailed description of the sound spatial distribution. There are currently two main techniques suitable for performing such analysis, either using a PU probe or a 3D sound intensity probe. This paper aims to provide an overview of the two techniques along with experimental evidence to thoroughly investigate their advantages and limitations. It is shown that the colormaps of normal sound intensity can be very useful, especially when the main sound sources are captured within the measured surface. On the other hand, the visualization of the sound intensity vector field can provide key insight on how sound interacts in complex measuring environments.