Accreditation to Supervise Research Jeroen Wackers - Online video
On November 19th, 2019, Jeroen Wackers (METHRIC team) defended his HDR on adaptive grid refinement for the simulation of complex flows.
on February 3, 2020
For numerical simulation in hydrodynamics, adaptive grid refinement is a technique that modifies, during a computation, the mesh which serves as a basis for the simulation, dependent on the requirements of the flow. The mesh is the subdivision of the computational domain, which enables the discretisation of the flow equations. A fine division provides results with a high level of precision, but is costly in terms of computational effort. To obtain the maximum efficiency for the simulations, it is therefore useful to place the finest grid only where this is needed to capture the flow features. Adaptive grid refinement allows us to perform this operation automatically.
For the simulation of complex flows, both in research and industry environments, adaptive grid refinement is becoming an essential tool. On one side, adaptation makes it possible to reliably generate meshes which resolve all the details of a complex flow. And on the other hand, it facilitates the creation of meshes for large series of computations, launched and treated in automated loops. However, the development of adaptive mesh refinement methods capable of operating in these environments, is a difficult challenge which requires an integration with the other capabilities of the flow solver, a significant investment for increasing the robustness of the method, as well as the creation of reliable user instructions and guidelines.
Since his arrival at the LHEEA laboratory in 2007, Jeroen Wackers studied and developed adaptive grid refinement in the context of the ISIS-CFD Navier-Stokes solver, created by the METHRIC team at LHEEA and commercialised in collaboration with NUMECA International, as part of the FINE/Marine simulation suite. This HDR is a reflection on this work, that analyses its position on the frontier between research and industrial application, the choices which were made during the development, and their consequences for the evolution of the method. The study finally considers the different types of applications which become possible thanks to such a method of grid adaptation, by studying a number of representative examples.
