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arXiv · 2301.01426

Iterative two-level algorithm for nonsymmetric or indefinite elliptic problems

Ming Tang·Xiaoqing Xing·Ying Yang·Liuqiang Zhong
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Abstract

In this paper, a new iterative two-level algorithm is presented for solving the finite element discretization for nonsymmetric or indefinite elliptic problems. The iterative two-level algorithm uses the same coarse space as the traditional two-grid algorithm, but its ``fine space'' uses the higher oder finite element space under the coarse grid. Therefore, the iterative two-level algorithm only needs one grid, and the computational cost is much lower than the traditional iterative two-grid algorithm. Finally, compared with the traditional two-grid algorithm, numerical experiments show that the computational cost is lower to achieve the same convergence order.

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Ming Tang, Xiaoqing Xing, Ying Yang, Liuqiang Zhong. 2023-01-04. Iterative two-level algorithm for nonsymmetric or indefinite elliptic problems. https://arxiv.org/abs/2301.01426

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