Alapfogalmak
This article presents a refined convergence analysis for a second-order accurate in time, fourth-order finite difference numerical scheme for the 3D Cahn-Hilliard equation, with an improved convergence constant.
Kivonat
The article focuses on the convergence analysis of a second-order accurate in time, fourth-order finite difference numerical scheme for the 3D Cahn-Hilliard equation.
Key highlights:
- The authors apply a modified backward differentiation formula (BDF2) temporal discretization and include a Douglas-Dupont artificial regularization to ensure energy stability.
- A standard application of discrete Gronwall inequality leads to a convergence constant dependent on the interface width parameter ε in an exponential singular form. The authors aim to obtain an improved estimate with a polynomial dependence on ε.
- To achieve this, the authors establish uniform in time functional bounds of the numerical solution, including higher order Sobolev norms, as well as bounds for the first and second order temporal difference stencils.
- The authors apply a spectrum estimate for the linearized Cahn-Hilliard operator, which leads to the refined error estimate.
- A 3D numerical example is presented to validate the theoretical analysis.