Adaptive Ch Method with Local Coupled Multiquadrics for Solving Partial Differential Equations

Ahmed E. Seleit

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arXiv · 2511.14929

Adaptive Ch Method with Local Coupled Multiquadrics for Solving Partial Differential Equations

Ahmed E. Seleit

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Abstract

We present a new adaptive collocation scheme for solving partial differential equations based on Local Coupled Multiquadrics (LCMQs) within a covers-and-nodes framework. The method, referred to as the Adaptive Ch Method, automatically prioritizes adjusting the local cover size C then refines local nodal spacing h to achieve a prescribed tolerance. Numerical examples for one- and two-dimensional Poisson problems demonstrate accurate solutions across a wide range of shape parameter values, while preserving the advantages of local collocation. The proposed approximation approach is truly meshless, requiring no element, connectivity or continuity to construct trial functions or weights.

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Ahmed E. Seleit. 2025-11-18. Adaptive Ch Method with Local Coupled Multiquadrics for Solving Partial Differential Equations. https://arxiv.org/abs/2511.14929

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