Workshop on Fluid Dynamics and Energy

8:30 am — Coffee

09:00 – 10:00 am — Emmanuel Grenier, École normale supérieure de Lyon, Lyon, France

  • Title: Instability of shear layers and Prandtl’s boundary layers
  • Abstract: The aim of this talk is to review recent results on the nonlinear instabilities of shear layers and on Prandtl’s boundary layers, and in particular to describe secondary instabilities which lead to new and unexpected sublayers. This is based on joint works with Dongfen Bian.

10:00-10:30 am — Break

10:30 – 11:30 am — Dongfen Bian, Beijing Institute of Technology, Beijing, China

  • Title: Asymptotic behaviour of solutions of the linearized Euler equations near a shear layer.
  • Abstract: The aim of this talk is to review recent results on the asymptotic behavior of solutions for the linearized incompressible Euler equations near a shear layer, and in particular to describe the evolution of the vorticity.

11:30 – 13:30 am — Lunch

13:30 – 14:30 pm — Khaled Saleh, University Claude Bernard, Lyon, France

  • Title: Analysis and numerical approximation of a compressible multiphase flow model.
  • Abstract: A multiphase flow is a flow involving species in different states of matter (gas, liquid, solid), or species in the same state but with different chemical properties (immiscible liquid-liquid mixtures, for example). Numerical simulation of such flows has many industrial applications: nuclear industry, oil industry, volcanology.

    In this talk, I’ll consider a so-called averaged multi-fluid model to model the evolution of a mixture of N compressible phases, N being arbitrary. Conceived as an extension of the famous Baer-Nunziato two-phase model, the N-phase model consists of N compressible Euler systems coupled by non-conservative terms and relaxation source terms whose role is to bring the phases in presence towards a mechanical and thermodynamic equilibrium. First, I’ll present the main properties of the model (hyperbolicity, entropy inequality, symmetrizability), then I’ll introduce a so-called Suliciu relaxation scheme for approximating the model’s solutions. We’ll see that this scheme provides a relatively accurate approximation of the solutions, despite being of order 1. We’ll also see that it verifies at the discrete level stability properties similar to those of the continuous model: positivity of the densities and statistical phase fractions, discrete entropy inequalities.

14:30-15:00 pm — Break

15:00 – 16:00 pm — Yacine Addad, Khalifa University, United Arab Emirates.

  • Title: Advancing Safety in Nuclear Power Plants: Harnessing CFD for Severe Accidents Analysis
  • Abstract: The forthcoming presentation will furnish a synopsis of recent Computational Fluid Dynamics (CFD) investigations undertaken within the framework of the ongoing projects under the Emirates Nuclear Technology Center (ENTC). Its primary aim is to evaluate the approach’s capabilities, discern its limitations, and explore avenues for potential enhancement.