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arXiv · 2605.30037

A novel mixed spectral method with ball polynomials for the Biharmonic equation on a unit ball

Mengxue Gao·Bing Su·Jianwei Zhou
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Abstract

A novel mixed spectral-Galerkin method based on generalized ball polynomials is proposed for solving the biharmonic equation on a unit ball. By introducing an auxiliary variable to decouple the biharmonic equation into a system of second-order equations, the corresponding discrete scheme yields a strictly diagonal stiffness matrix, which significantly enhances the computational efficiency. Rigorous a-priori error estimates are established to demonstrate the exponential convergence rates in both the $L^2$- and $H^1$-norms. Extensive numerical experiments are conducted to verify the theoretical analysis and confirm the high efficiency and accuracy of the proposed scheme.

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Mengxue Gao, Bing Su, Jianwei Zhou. 2026-05-28. A novel mixed spectral method with ball polynomials for the Biharmonic equation on a unit ball. https://doi.org/10.1016/j.aml.2026.110102

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