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arXiv · 2607.15138

Translation of transient acoustic fields

Michael J. Carley
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Abstract

A method is presented for the translation of acoustic field data from a source to a target region. Field data are represented as spherical harmonic expansions on spheres surrounding the source and target regions respectively and expansions are translated using a ``point and shoot'' method using the Kirchhoff-Helmholtz integral to carry out an axial translation from one sphere to the other. The principal motivation for the method is its use in a time-domain Fast Multipole Method, and test cases reflective of this application are presented. The method converges to six digits for appropriate values of parameters and computational effort scales approximately as $N^{2}$ where $N$ is the order of spherical harmonic expansion for the field data.

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Michael J. Carley. 2026-07-16. Translation of transient acoustic fields. https://arxiv.org/abs/2607.15138

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