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arXiv · 0712.1699

Numerical quadratures for near-singular and near-hypersingular integrals in boundary element methods

Michael Carley
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Abstract

A method of deriving quadrature rules has been developed which gives nodes and weights for a Gaussian-type rule which integrates functions of the form: f(x,y,t) = a(x,y,t)/((x-t)^2+y^2) + b(x,y,t)/([(x-t)^2+y^2]^{1/2}) + c(x,y,t)\log[(x-t)^2+y^2]^{1/2} + d(x,y,t), without having to explicitly analyze the singularities of $f(x,y,t)$ or separate it into its components. The method extends previous work on a similar technique for the evaluation of Cauchy principal value or Hadamard finite part integrals, in the case when $y\equiv0$. The method is tested by evaluating standard reference integrals and its error is found to be comparable to machine precision in the best case.

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Michael Carley. 2007-12-11. Numerical quadratures for near-singular and near-hypersingular integrals in boundary element methods. https://doi.org/10.3318/pria.2008.109.1.49

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