Rigorous HHO Optimal Error Estimates and Simulation of FitzHugh-Nagumo Model
摘要
In this paper, we develop and analyze a hybrid high-order (HHO) numerical scheme for the FitzHugh-Nagumo (FHN) reaction-diffusion model which arises in neuronal dynamics, cardiac physiology, and cell division. The proposed method combines HHO for spatial discretization with the BDF2 scheme for time integration, achieving higher-order accuracy and stability. The method supports an arbitrary order of approximation and general polytopal meshes, making it highly flexible. The key ingredients involve local reconstruction and high-order stabilization terms, ensuring robustness. A Lyapunov functional is introduced to establish boundedness, and an elliptic-type projection is used for