Equal order stabilized finite elements with Nitsche for stationary Navier-Stokes problem with slip boundary conditions : a priori and a posteriori error analysis
Aparna Bansal, Nicolás Barnafi, Rodolfo Araya, Dwijendra Narain Pandey
TL;DR
This work develops and analyzes an equal-order stabilized finite element method for the stationary incompressible Navier–Stokes equations with slip boundary conditions, employing Nitsche's method to impose slip on complex boundaries. The authors establish well-posedness and stability of the discrete problem for symmetric, skew-symmetric, and incomplete Nitsche variants, and derive rigorous a priori error bounds with optimal convergence under standard regularity assumptions. They also formulate residual-based a posteriori error estimators, proving reliability and efficiency, and validate the theory with extensive numerical experiments including analytic solutions, the lid-driven cavity, adaptive refinement on non-convex domains, and 3D flow around a cylinder. The results demonstrate the method’s robustness, accuracy, and adaptability, offering a practical framework for slip-boundary simulations on complex geometries and adaptive meshes. Future work targets unsteady Navier–Stokes extensions and parameter-robust preconditioning to improve scalability.
Abstract
In this work, we extend the equal-order stabilized scheme discussed in [Franca et al., Comput. Methods Appl. Mech. Engrg. 99 (1992) 209-233] to accommodate slip (i.e., Navier) boundary conditions for the stationary Navier-Stokes equations. Our analysis presents a robust formulation for implementing slip boundary conditions using Nitsche's method on arbitrarily complex boundaries. The well-posedness of the discrete problem is established under mild assumptions together with optimal convergence rates for the approximation error. Furthermore, we establish the efficiency and reliability of residual-based a posteriori error estimators for the stationary discrete problem. Several well-known numerical tests validate our theoretical findings. The proposed method fits naturally within the framework of finite element implementation, offering both accuracy and enhanced flexibility in the selection of finite element pairs.
