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arXiv · 1902.02925

Boundary regularised integral equation formulation of the Helmholtz equation in acoustics

Q. Sun·E. Klaseboer·B. C. Khoo·D. Y. C. Chan
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Abstract

A boundary integral formulation for the solution of the Helmholtz equation is developed in which all traditional singular behaviour in the boundary integrals is removed analytically. The numerical precision of this approach is illustrated with calculation of the pressure field due to radiating bodies in acoustic wave problems. This method facilitates the use of higher order surface elements to represent boundaries, resulting in a significant reduction in the problem size with improved precision. Problems with extreme geometric aspect ratios can also be handled without diminished precision. When combined with the CHIEF method, uniqueness of the solution of the exterior acoustic problem is assured without the need to solve hypersingular integrals.

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Q. Sun, E. Klaseboer, B. C. Khoo, D. Y. C. Chan. 2019-02-08. Boundary regularised integral equation formulation of the Helmholtz equation in acoustics. https://doi.org/10.1098/rsos.140520

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