1. Introduction

Mesh adaptation helps the user to provide the most reliable calculations possible with respect to discretization errors induced by the finite element resolution method.

We will not detail the principle of adaptation in this document and refer the reader to the [U2.08.01] document. We are just reminding you of a few things.

Schematically, a mesh adaptation iteration is presented as in the figure below. The software calculates the numerical solution on mesh number \(k\), then deduces the values of the error indicator over the entire mesh. Based on the knowledge of the mesh number \(k\) and the indicator number \(k\), the mesh adaptation software HOMARD, creates the new mesh number \(k+1\).

Figure 1: Iteration of mesh adaptation

For a static calculation, this means seeking to improve the solution by a succession of calculations on different meshes. For a transitory time calculation, the calculation is suspended at a given moment; the mesh is adapted; the calculation is resumed on the new mesh. That is the situation we are addressing here. In fact, in the case of resolving a non-linear transient, restarting the calculation is not necessarily easy. The objective of this document is to help the user to implement this type of modeling.