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arXiv · 2309.15346

Efficient implementation of the hybridized Raviart-Thomas mixed method by converting flux subspaces into stabilizations

Sreevatsa Anantharamu·Bernardo Cockburn
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Abstract

We show how to reduce the computational time of the practical implementation of the Raviart-Thomas mixed method for second-order elliptic problems. The implementation takes advantage of a recent result which states that certain local subspaces of the vector unknown can be eliminated from the equations by transforming them into stabilization functions; see the paper published online in JJIAM on August 10, 2023. We describe in detail the new implementation (in MATLAB and a laptop with Intel(R) Core (TM) i7-8700 processor which has six cores and hyperthreading) and present numerical results showing 10 to 20% reduction in the computational time for the Raviart-Thomas method of index $k$, with $k$ ranging from 1 to 20, applied to a model problem.

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Sreevatsa Anantharamu, Bernardo Cockburn. 2023-09-27. Efficient implementation of the hybridized Raviart-Thomas mixed method by converting flux subspaces into stabilizations. https://arxiv.org/abs/2309.15346

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