2024/03/07 by Fenghua Tong, Tong, Fenghua, Yongyong Cai +1 · 2 citations
Mathematics · #Gas Dynamics and Kinetic Theory #Numerical methods in inverse problems #Spectral Theory in Mathematical Physics
paper · pdf · doi:10.48550/arxiv.2403.04291
We propose and analyze a novel approach to construct structure preserving approximations for the Poisson-Nernst-Planck equations, focusing on the positivity preserving and mass conservation properties. The strategy consists of a standard time marching step with a projection (or correction) step to satisfy the desired physical constraints (positivity and mass conservation). Based on the L2 projection, we construct a second order Crank-Nicolson type finite difference scheme, which is linear (exclude the very efficient L2 projection part), positivity preserving and mass conserving. Rigorous error estimates in L2 norm are established, which are both second order accurate in space and time. The other choice of projection, e.g. H1 projection, is discussed. Numerical examples are presented to verify the theoretical results and demonstrate the efficiency of the proposed method.