ECFD workshop, 7th edition, 2024

Description

• Event from 22th of January to 2nd of February 2024
• Location: Hôtel Club de la Plage, Merville-Franceville, near Caen (14)
• Two types of sessions:
  • common technical presentations: roadmaps, specific points
  • mini-workshops. Potential workshops are listed below
• Free of charge
• More than 70 participants from academics, HPC center/experts and industry.

• Objectives
  • Bring together experts in high-performance computing, applied mathematics and multi-physics CFDs
  • Identify the technological barriers of exaflopic CFD via numerical experiments
  • Identify industrial needs and challenges in high-performance computing
  • Propose action plans to add to the development roadmaps of the CFD codes

Agenda

Thematics / Mini-workshops

These mini-workshops may change and cover more or less topics. This page will be adapted according to your feedback.

To come...

Projects

Numerics - S. Mendez, IMAG & G. Balarac, LEGI

WIP N1: High-Order schemes for Navier-Stokes - M. Bernard & G. Balarac (LEGI) & G. Lartigue (Total Eneriges)

Finite Volumes method. Distinction between integrate and pointwise quantities. Spacial accuracy depend on ability to evaluate accurately fluxes, starting from integrated quantities. Accurate evaluation of fluxes through interface of each control volume (CV). OK inside the domain, but chalenging in case of boundary conditions : by definition non uniformity of the stencil. BC on faces instead of nodes. Enforcement of the BC by modifying the normal component of the wall gradient in order to evaluate accurate diffusif flux. Treatment of inlet BC by integrating convective flux through each boundary-facelet.

N6: Electrodeformation of red blood cells, extension to 3D and improved accuracy at membrane - A. Spadotto & S. Mendez (IMAG), M. Bernard (LEGI)

The Leaky Dielectric Model is a popular framework to describe electric stresses over micro-scale membranes. We have adopted it to simulate the effect of a DC electric field on a red blood cell using the YALES2BIO solver. The goal of the project is to reproduce the electric charging process of the membrane, as well as the resulting stresses, which may yield to electrodeformation of the cell. From the point of view of the implementation, the grid is represented by a 2D surface mesh embedded in a 3D eulerian grid. The need to make variables stored on the surface interact with quantities stored on the Eulerian grid calls for a proper bidirectional 2D-membrane/3D-grid dynamic connectivity. The advancement of theis task during this ECFD has led to the first 3D simulation of a charging fixed spherical shell. Moreover, the estimation of grid variables on elements cut by the membrane has been improved thanks to a High-Order extrapolation. The latter has been successfully tested on 2D configurations. The project opens the way for a series of validation tests. In particular, future work will demand treatment of instabilities emerging in symmetrical configurations.

T4: Atmospheric solver

Wind turbines, bigger and bigger, are now influenced by atmospheric flows. An atmospheric solver has already been developed in YALES2 to represents some of its effects (Coriolis, veer, thermal stratification). In this continuum, the project has been divided into two work-packages. - Work-package 1: The use of the Variable density solver (VDS). Before ECFD7, thermal stratification was taken into account using the Boussinesq buoyancy approximation within the incompressible solver framework. Now, VDS can be used, taking into account all thermal effect. Results are promissing. - Work-package 2: Wall law velocity filtering. Wall law are using velocity at the first grid node to compute wall shear stress. Before ECFD7, atmospheric wall law were using the local velocity, leading sometimes to convergence errors. Now a gather-scatter filter can be used to average velocity (and temperature) at first grid node.