The governing equations for supercritical carbonation incorporating calcium dissolution (Part I) are complex and can only be solved numerically. This paper develops a multiphysics numerical model based on the theoretical framework presented in Part I. A supercritical carbonation experiment on cement paste was conducted to validate both the numerical and theoretical models. Additionally, simulations with and without calcium dissolution were compared. The results indicate that incorporating calcium dissolution improves simulation accuracy by approximately 20% compared to previous studies. This study provides a more precise approach for predicting and characterizing the supercritical carbonation process of cement-based materials.