Superconvergent quadriatic finite element on uniform tetrahedral meshes

Fuente: arXiv
Gespeichert in:
Bibliographische Detailangaben
Hauptverfasser: Huang, Yunqing, Zhang, Shangyou
Format: Preprint
Veröffentlicht: 2025
Schlagworte:
Online-Zugang:
Tags: Tag hinzufügen
Keine Tags, Fügen Sie den ersten Tag hinzu!
_version_ 1866918058995482624
author Huang, Yunqing
Zhang, Shangyou
author_facet Huang, Yunqing
Zhang, Shangyou
contents By a direct computation, we show that the $P_2$ interpolation of a $P_3$ function is also a local $H^1$-projection on uniform tetrahedral meshes, i.e., the difference is $H^1$-orthogonal to the $P_2$ Lagrange basis function on the support patch of tetrahedra of the basis function. Consequently, we show the $H^1$ and $L^2$ rconvergence of the $P_2$ Lagrange finite element on uniform tetrahedral meshes. Using the standard 20-points Lagrange $P_3$ interpolation, where the 20 nodes are exactly some $P_2$ global basis nodes, we lift the superconvergent $P_2$ finite element solution to a quasi-optimal $P_3$ solution on each cube. Numerical results confirm the theory.
format Preprint
id arxiv_https___arxiv_org_abs_2506_12407
institution arXiv
publishDate 2025
record_format arxiv
spellingShingle Superconvergent quadriatic finite element on uniform tetrahedral meshes
Huang, Yunqing
Zhang, Shangyou
Numerical Analysis
65N15, 65N30
By a direct computation, we show that the $P_2$ interpolation of a $P_3$ function is also a local $H^1$-projection on uniform tetrahedral meshes, i.e., the difference is $H^1$-orthogonal to the $P_2$ Lagrange basis function on the support patch of tetrahedra of the basis function. Consequently, we show the $H^1$ and $L^2$ rconvergence of the $P_2$ Lagrange finite element on uniform tetrahedral meshes. Using the standard 20-points Lagrange $P_3$ interpolation, where the 20 nodes are exactly some $P_2$ global basis nodes, we lift the superconvergent $P_2$ finite element solution to a quasi-optimal $P_3$ solution on each cube. Numerical results confirm the theory.
title Superconvergent quadriatic finite element on uniform tetrahedral meshes
topic Numerical Analysis
65N15, 65N30
url https://arxiv.org/abs/2506.12407