其他摘要：Using weak formulations and finite elements to solve heat conduction problems with phase change requires the resolution of a non-linear system of equations in the nodal temperatures at each time step. The choice of a good aproximation to the tangent matrix is critical when the latent heat is comparatively large. In this work we derive an exact expression for the tangent matrix. We develope a method to calculate this matrix and analyze the behaviour of its terms for differents values of the physical parameters of the system. Finally, several numerical examples are shown.
