Patch near field acoustic holography based on particle velocitymeasurements

摘要

Patch near field acoustic holography (PNAH) based on sound pressure measurements makes itpossible to reconstruct the source field near a source by measuring the sound pressure at positionson a surface that is comparable in size to the source region of concern. Particle velocity is analternative input quantity for NAH, and the advantage of using the normal component of the particlevelocity rather than the sound pressure as the input of conventional spatial Fourier transform basedNAH and as the input of the statistically optimized variant of NAH has recently been demonstrated.This paper examines the use of particle velocity as the input of PNAH. Because the particle velocitydecays faster toward the edges of the measurement aperture than the pressure does and because thewave number ratio that enters into the inverse propagator from pressure to velocity amplifies highspatial frequencies, PNAH based on particle velocity measurements can give better results than thepressure-based PNAH with a reduced number of iterations. A simulation study, as well as anexperiment carried out with a pressure-velocity sound intensity probe, demonstrates thesefindings.