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arXiv · 1301.6860

Convergence analysis of a family of 14-node brick elements

Zhaoliang Meng·Zhongxuan Luo·Dongwoo Sheen·Sihwan Kim
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Abstract

In this paper, we will give convergence analysis for a family of 14-node elements which was proposed by I. M. Smith and D. J. Kidger in 1992. The 14 DOFs are taken as the value at the eight vertices and six face-centroids. For second-order elliptic problem, we will show that among all the Smith-Kidger 14-node elements, Type 1, Type 2 and type 5 elements can get the optimal convergence order and Type 6 get lower convergence order. Motivated by the proof, we also present a new 14-node nonconforming element. If we change the DOFs into the value at the eight vertices and the integration value of six faces, we show that Type 1, Type 2 and Type 5 keep the optimal convergence order and Type 6 element improve one order accuracy which means that it also get optimal convergence order.

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Zhaoliang Meng, Zhongxuan Luo, Dongwoo Sheen, Sihwan Kim. 2013-01-29. Convergence analysis of a family of 14-node brick elements. https://doi.org/10.1016/j.cam.2016.01.023

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