Automotive NVH

Sound Intensity

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Sound Intensity is the measurment of acoustic energy radiated by an object. Sound Intensity can be used for localize and visualize sound sources. The sources can be quantified and analysed. Mainly the measurements are used for mapping a object to detect hotspots. Other application Sound Intensity are used for are for example: troubleshooting, finding acoustic leakages and determination of Sound Power.

Any sound field is described by two complementary acoustic properties, the scalar value 'sound pressure' and the vector value 'acoustic particle velocity'. The product of sound pressure and acoustic particle velocity is giving the Sound Intensity. Before particle velocity sensors became available, a finite difference approximation of the pressure gradient using two phase matched pressure transducers (the so called p-p method) estimated the particle velocity signal. The Microflown PU probes directly measure both quantities in one spot. Due to the near field benifits using the direct measurement of the directional particle velocity measurements can be undertaken in real operational situation even in cases with a high pressure over intensity ratio. PU probes are very small and broad banded without any spacing requirements, facilitating the ease of use significantly.

Features

  • Frequency range 20Hz - 20kHz
  • Both quantities, sound pressure and particle velocity, directly measured at one point
  • Low suscepebility to background noise and reflections
  • No need for anechoic room or anechoic conditions
  • High spatial resolution
Sound Intensity is the measure of acoustic energy