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arXiv · cs/0205020

A quasi-RBF technique for numerical discretization of PDE's

Abstract

Atkinson developed a strategy which splits solution of a PDE system into homogeneous and particular solutions, where the former have to satisfy the boundary and governing equation, while the latter only need to satisfy the governing equation without concerning geometry. Since the particular solution can be solved irrespective of boundary shape, we can use a readily available fast Fourier or orthogonal polynomial technique O(NlogN) to evaluate it in a regular box or sphere surrounding physical domain. The distinction of this study is that we approximate homogeneous solution with nonsingular general solution RBF as in the boundary knot method. The collocation method using general solution RBF has very high accuracy and spectral convergent speed and is a simple, truly meshfree approach for any complicated geometry. More importantly, the use of nonsingular general solution avoids the controversial artificial boundary in the method of fundamental solution due to the singularity of fundamental solution.

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BibTeXRIS

W. Chen. 2002-05-14. A quasi-RBF technique for numerical discretization of PDE's. https://arxiv.org/abs/cs/0205020

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