Effect of horizontal meshing on dissipation in a 3D ocean model

Details

Supervisors

Hanert, Emmanuel ; Lambrechts, Jonathan ; Legat, Vincent

Faculty

Ecole polytechnique de Louvain

Degree label

Master [120] : ingénieur civil mécanicien, à finalité spécialisée

Abstract

The field of numerical simulation has been in constant progression for the last several decades. One important domain for which such simulations can be interesting to perform concerns the submarine processes, occurring in the seas and the oceans of the world. Those numerical analysis may be performed using finite element methods, which requires a discretization of the space. Several techniques to perform such a task are available, and different coordinate systems can be distinguished. This thesis will be interested in one system in particular, called the $z$ coordinates, which may happen to be more dissipative. In this report, this decay of energy have been analyzed and quantified on a simple simulation setting. As this decay has been considered to be significant, a new remeshing strategy have been developed . Although a solution could be to refine the mesh on strongly dissipative zone, the technique implemented in the context of this thesis tries to lower this energy dissipation while keeping the size of the elements similar. This lead to the creation what has been referred to as the contour-fitted meshes. Although we did not have the time to test this new kind of meshes on real-life test cases, the results obtained on the simple setting are a good reason to expect a notable and positive impact of their usage. It is in consequence to be hoped that further work will be performed in order to test this concept in a broader perspective.