TY - JOUR T1 - Achieving Superconvergence by One-Dimensional Discontinuous Finite Elements: Weak Galerkin Method AU - Ye , Xiu AU - Zhang , Shangyou JO - East Asian Journal on Applied Mathematics VL - 3 SP - 590 EP - 598 PY - 2022 DA - 2022/04 SN - 12 DO - http://doi.org/10.4208/eajam.030921.141121 UR - https://global-sci.org/intro/article_detail/eajam/20408.html KW - Finite element, weak Galerkin, stabilizer free. AB -
A simple stabilizer free weak Galerkin (SFWG) finite element method for a one-dimensional second order elliptic problem is introduced. In this method, the weak function is formed by a discontinuous $k$-th order polynomial with additional unknowns defined on vertex points, whereas its weak derivative is approximated by a polynomial of degree $k+1.$ The superconvergence of order two for the SFWG finite element solution is established. It is shown that the elementwise lifted $P_{k+2}$ solution of the $P_k$ SFWG one converges at the optimal order. Numerical results confirm the theory.