TY - JOUR T1 - Stabilized Continuous Linear Element Method for the Biharmonic Problems AU - Cai , Ying AU - Guo , Hailong AU - Zhang , Zhimin JO - Communications in Computational Physics VL - 2 SP - 498 EP - 520 PY - 2025 DA - 2025/02 SN - 37 DO - http://doi.org/10.4208/cicp.OA-2023-0302 UR - https://global-sci.org/intro/article_detail/cicp/23871.html KW - Biharmonic problems, gradient recovery, superconvergence, linear finite element. AB -

In this paper, we introduce a new stabilized continuous linear element method for solving biharmonic problems. Leveraging the gradient recovery operator, we reconstruct the discrete Hessian for piecewise continuous linear functions. By adding a stability term to the discrete bilinear form, we bypass the need for the discrete Poincaré inequality. We employ Nitsche's method for weakly enforcing boundary conditions. We establish well-posedness of the solution and derive optimal error estimates in energy and $L^2$ norms. Numerical results are provided to validate our theoretical findings.