Inverse and Reciprocity Methods for Machinery Noise Source Characterization and Sound Path Quantification Part 2: Transmission Paths

A Note on Finite Difference Estimation of Acoustic Particle Velocity

“…Because of the directional information, measurements of the particle velocity have also found applications in room acoustics [4], as already suggested in reference [1]. Yet another application is in analyzing large, complicated sources of noise; a small omnidirectional source with a strength that is measured on-line would be very useful in reciprocity experiments for characterizing machinery noise sources [5,6]. However, it is more di$cult to measure the particle velocity than the sound pressure.…”

Use of a reciprocity technique to measure the radiation efficiency of a vibrating structure

“…It is based on subdividing the radiating surface into small areas radiating as correlated or uncorrelated monopoles and in an experimental characterisation of the monopole properties through reciprocity. The extension of the reciprocity principle to include the vibrating structure, as demonstrated by Lyamshev, is also discussed in [10] and further applications are detailed by Verheij in [12] and [13]. In the examples summarised in the above-mentioned papers it is also shown how reciprocity can be of support in developing and applying inverse force identification techniques.…”

On the Characteristic Power of Structure-Borne Sound Sources

“…Verheij's equivalent forces have been used successfully for rank ordering of transmission paths [6]. However, they are in general dependent on the receiver structure, and therefore not truly independent.…”