End of the ASTURIES project: new models for fluid flow with turbulence
The scientific challenge led by Rémi Manceau, CNRS research director at the Laboratory of Mathematics and their Applications in Pau (LMAP), and a CNRS-Inria-UPPA team in partnership with CEA Cesta and IFPEN has led to the development of models that save computing time.
Fluid flows (usually water or air) are complex phenomena due to the turbulence associated with them. People have been trying to understand them since Leonardo da Vinci, as they have numerous industrial and environmental applications. However, the experimental approach using wind tunnels is extremely expensive, and the numerical approach requires computing power that does not yet exist.
The idea behind the project was therefore to try to model this turbulence without having to calculate every detail. How? By developing agile approaches that adapt the model's precision to the situation during calculation. In other words, a dynamic compromise had to be found between calculation cost and physical representation.
Focusing on both modeling and calculation accuracy
In terms of the physical model, the team, consisting of a doctoral student and a postdoctoral researcher, developed new approaches that enable automatic switching between a “coarse” approach and a highly accurate approach during the calculation. A new model was established that physically represents what happens in different regions of turbulence and connects them.
In terms of the numerical scheme, the idea was to achieve the desired accuracy in the desired location. Work focused on how to write the equations and algorithmic efficiency so that the calculations would not take too long. With the CEA, the team was able to write very precise schemes for the turbulence models developed for the first time. With IFPEN, the mesh used made it possible to describe turbulence locally using a more precise scheme, and the chair was able to do this within a commercial industrial code.
The next step was to confirm these positive results on a completely different test case, that of crossflow jet (i.e., like a geyser in a sea current, or inside an aircraft engine combustion chamber), in comparison with the experimental data made available in the project. This test validated the self-adaptive models established by the team, a world first.
Scientific publications have been released in leading journals in the field, such as Flow, Turbulence and Combustion or Physics of Fluids, with another currently in progress.
Photos: Inria
The I-SITE Energy and Environment Solutions (E2S) is a research consortium involving UPPA, INRAE, Inria and CNRS that has obtained funding from the Investissements d'Avenir programme thanks to the I-SITE (Initiative Sciences, Innovation, Territories, Economy) label of university excellence.
Between 2017 and 2024, the I-SITE has financed a number of partnership research projects, including ‘exploratory’ projects designed to develop innovative topics and reduce technological barriers.
