The idea of the SIG was launched by Julian Hunt, after the successful PEPIT/ERCOFTAC workshop held in Ecole Centrale de Lyon, May 9-12, 2000, "Two-point closures and their applications" (see Godeferd, Cambon & Scott, J. Fluid Mech., 436, 2001, 393-407).
"Two-point closures" (or TPC), however, is perhaps too restricted a topic, and the range of activities of this SIG will in fact cover various multi-scale, anisotropic and multi-modal aspects, possibly in connection with strong body forces and mean gradients. Inhomogeneity, especially induced by solid walls, will be addressed too.
In addition to classic TPC used in statistical theory, linear theory ("Rapid Distortion Theory" or RDT, stability analysis), weakly nonlinear theory (e.g. wave-turbulence), low-dimension dynamical models (e.g. using pod), shell-models, Lagrangian models for dispersion (e.g. using Kinematic Simulation, or KS, RDT, nonlinear TPC), have to be considered from a pragmatic view-point, in order, for instance, to suggest guidelines to improve simpler models (single-point closures in RANS, subgrid scale models for LES).
Use of symmetry groups (Lie group, SO(3) ), in agreement with both dynamical equations and boundary layers, is very promising. The SO(3) symmetry group and spherical harmonic expansions, which begin to be used in the "intermittency and scaling" community, have to be revisited in connection with fully anisotropic spectral description used for two decades in the team "Ondes et Turbulence", LMFA. The above list of tools is not exhaustive.
The SIG 35: "Multi-point Turbulence Structure and Modeling" is currently focused on the following topics:
Workshop on "Multiscale and directional approach to single-phase and two-phase flows" Location: Ecole Centrale de Lyon, France Date: 4th - 7th May 2020 SIG: SIG35, SIG39, SIG50, PC Henry Bénard Organisers: Mikhael Gorokhovski ( LMFA, Ecole Centrale de Lyon, France) , Carlo4 May 2020
ERCOFTAC SIG50 and SIG35 Workshop Turbulence and Instabilities in Plasma Flows 25th - 27th November 2019 Écully, France SCIENTIFIC SCOPE: Plasma flows are ubiquitous in nature – pervading the Earth’s environment through the interplanetary space – while hot and cold plasmas are operated25 Nov 2019
Astroflu IV - Organized by Henri Bénard Pilot Center, SIG 35 and SIG 4. January 23-24 2019, École Centrale de Lyon Motivations and Objectives: The two first local events ‘ASTROFLU’ were principally organised by the Henri Bénard PC in Lyon, 12-13/11/2008 and 15/12/2011. The third one, which took23 Jan 2019
Date: 01/07/2018 Location: École centrale de Lyon, Écully - Amphi 1 Organisers: Claude Cambon, Fabien Godeferd PC Henri Benard Friday June, 1st 10:30 CHB Introductory session – C. Cambon & F.S. Godeferd 11:00 Special seminar on Henri Bénard history and scientific legacy “Henri1 Jun 2018
Date : 30-31/5/2018 Location : École Centrale de Lyon - Amphi 1, 36 avenue Guy de Collongue, Écully, France Organisers : Christos Vassilicos and Claude Cambon Workshop: SIG35 This workshop is partly a follow-up of previous ones, in D’Alembert, Paris, in May 2015 and May 2016 and in29 May 2018
The new issue of ERCOFTAC Bulletin has been released ! Table of contents is available here1 Aug 2019