Résolution d'écoulements instationnaires et adjoints

Hubert Alcin (INRIA, BP93, 06902 Sophia-Antipolis, France)

PhD thesis, University of Nice, 2012 (167 pages, in French)

Abstract: This work focuses on three themes: multi-level algorithms, automatic differentiation and mesh adaptation. The first theme focuses on the development of an algorithm for resolution by coarse grid for elliptic, advection problem and compressible Navier-Stokes equations in 3D . The algorithm combines a coarse grid equation preconditioning with a decomposition of Schwarz. Experiments are carried out on severals processors up to 1024. A significant acceleration has been obtained (factor 2 CPU for calculations simulations of Large Structures). The second theme focuses on the differentiation of MPI codes, it helped extend the analysis of the dependence context to MPI and study problems in differentiating codes that use dynamic memory allocation. We differentiate the simulation code AIRONUM (developed in the team) in order to calculate the adjoint model. The third theme relates to the application of adjoint state in the mesh adaptation. It is based on a priori error analysis for the 3D unsteady com- pressible Navier Stokes model. It has been extended to the case of Large Eddy Simulation (LES) thanks to a new method focusing on error analysis of the gap between the continuous model of filtered Navier-Stokes and its discretization.

Keywords: Mesh adaptation, Adjoint, A priori error estimate, Navier-Stokes, Coarse grid, Multi-level, Automatic Differentiation, Tangent mode, Reverse mode.


@phdthesis{phdAlcin12,
  author = {Alcin, H.},
  title = {R{\'e}solution d'{\'e}coulements instationnaires et adjoints},
  type = {PhD},
  school = {Universit{\'e} de Nice Sophia-Antipolis},
  year = 2012
}