Novel linear, decoupled, and energy dissipative schemes for the Navier-Stokes-Darcy model and extension to related two-phase flow
Xiaoli Li, Jie Shen, Xinhui Wang
TL;DR
This work develops linear, decoupled prediction–correction schemes for the Navier–Stokes–Darcy model that guarantee dissipation of the original energy and require only linear solves with constant coefficients at each time step. A novel relaxation-based correction using a scalar factor $\xi$ enforces unconditional energy stability and boundedness of velocity and hydraulic head, with a rigorous error analysis provided for the first-order scheme. The methodology extends to the Cahn–Hilliard–Navier–Stokes–Darcy system, yielding a first-order scheme (and EMAC variants) that preserves the original energy dissipation. Numerical experiments, including convergence tests and multiphase flow scenarios, demonstrate accuracy, stability, and robustness across a range of challenging two-phase flow problems.
Abstract
We construct efficient original-energy-dissipative schemes for the Navier-Stokes-Darcy model and related two-phase flows using a prediction-correction framework. A new relaxation technique is incorporated in the correction step to guarantee dissipation of the original energy, thereby ensuring unconditional boundedness of the numerical solutions for velocity and hydraulic head in the $l^{\infty}(L^2)$ and $l^2(H^1)$ norms. At each time step, the schemes require solving only a sequence of linear equations with constant coefficients. We rigorously prove that the schemes dissipate the original energy and, as an example, carry out a rigorous error analysis of the first-order scheme for the Navier-Stokes-Darcy model. Finally, a series of benchmark numerical experiments are conducted to demonstrate the accuracy, stability, and effectiveness of the proposed methods.
