January - June 1999
Organisers: GF Hewitt (Imperial College), PA Monkewitz (Lausanne), N Sandham (QMW), JC Vassilicos (Cambridge)
Research Programme on Turbulence Symposium on TURBULENCE STRUCTURE Isaac Newton Institute for Mathematical Sciences, Cambridge, UK In association with ERCOFTAC March 15 - 19, 1999 |
Background Organisation Programme (updated 10/03/99) Further Information
Turbulence is characterised by a large number of weakly correlated motions on a wide range of length-and-time-scales and appears disordered but also contains long-lived organised elements. Indeed, recent numerical and experimental observations have revealed the spontaneous formation of little shear layers and vortex tubes which are surrounded by what appears as a random and shapeless sea in the small scales of the turbulence.
First of all, there is a need to establish the importance of these vortical structures. Could they be thought of as 'eigen-structures', what are their stability properties, their geometrical statistics, how do they interact or not interact with each other and with surrounding turbulence, and what are their dissipative properties? Are the near-singularities of the turbulence or the conjectured finite-time singularities related to vortical or other (e.g. straining) sructures, and if so what kind? What are the Eulerian and the Langrangian properties of such structures, and how do their conditional statistics relate to the well-established unconditional Eulerian and Lagrangian statistics (e.g. spectra, energy cascades up-and-down-scale, relative motions of particles) and the scaling properties of the entire flow? To what extent can turbulence be represented in terms of space-filling functions such as Fourier or Chebychev basis functions or is it necessary to work in terms of localised functions such as wavelets?
Can answers to the above questions, in particular those relating to energy transfer and dissipation, be used for novel turbulence modelling? Finally, and most importantly, what are the universal aspects of the statistical, structural and modelling facets of the turbulence problem, and how do they relate to each other?
This symposium will address the mathematical aspects of vortex dynamics including interactions between vortices and turbulence, representations of complex internal structure and connections to statistics and statistical modelling of turbulence. Developments in the study of university of small-scale turbulence will be emphasised.
The Symposium is being organised by J.C.R. Hunt and J.C. Vassilicos in collaboration with the other Organisers of the Isaac Newton Institute Research Programme on Turbulence and supported by the Scientific Advisory Committee of the Programme.
The Organisers of the INI Research Programme are as follows:
J.C. Vassilicos (DAMTP, Cambridge)
G.F. Hewitt (Imperial College, London)
N.D. Sandham (Queen Mary & Westfield College, London)
P.A. Monkewitz (EPF, Lausanne, Switzerland)
The Symposium will be held at the Isaac Newton Institute, 20 Clarkson Road, Cambridge CB3 0EH, UK (tel: 01223 335999, fax: 01223 330508.
08.30-09.15 Registration
09.15-09.30 HK Moffatt (Cambridge)
Welcome by Director
09.30-10.15 EA Novikov (California)
Vortical structure & modelling of turbulence
10.15-11.00 AB Tsinober (Tel-Aviv)
Vortex stretching & production of strain/dissipation
11.00-11.45 Coffee & Posters
11.45-12.30 Z Warhaft (Cornell)
The issue of local isotropy of velocity & scalar turbulent fields
12.30-14.00 Lunch
14.00-14.45 JG Brasseur (Pennsylvania State)
Transition from isotropic to shear-dominated vortex structure in
physical
& fourier space
14.45-15.30 JC Vassilicos (Cambridge)
Dynamics of near-singular vortex
15.30-15.50 P Chainais (Ecole Normale Superieure)
Intermittency & coherent structures in a swirling flow: a wavelet
analysis of joint pressure and velocity measurements
15.50-16.30 Tea & Posters
16.30-16.50 BI Shraiman (Bell Laboratories)
Lagrangian tetrad dynamics & the statistical geometry of turbulence
16.50-17.10 E Gaudin (LPMMH-ESPCI)
Influence of coherent structures on velocity and passive scalar
statistics
in turbulent regime
16.50-17.40 General Discussion
17.40-19.00 Wine Reception
09.00-09.45 HK Moffatt (Cambridge)
A singularity of the Navier Stokes equations associated with vortex
interactions?
09.45-10.30 JD Gibbon (Imperial)
Vorticity alignment in the three-dimensional Euler & Navier-Stokes
equations
10.30-10.50 Y Kimura (Nagoya)
Gradient enhancement & filament ejection for non-uniform elliptic
vortex in 2D turbulence
10.50-11.30 Coffee & Posters
11.30-12.15 CF Barenghi (Newcastle)
Vortex lines & vortex tangles in superfluid helium
12.15-12.35 C Baudet (Ecole Normale Superieure)
Experimental detection of coherent vorticity structures using a full
spectral technique
12.35-14.00 Lunch
14.00-14.45 RM Kerr (NCAR)
Applications of vortex dynamics to MHD current dynamics
14.45-15.30 Y Fukumoto (Kyushu)
Large motion & expansion of a viscous vortex ring
15.30-15.50 H Hanazaki (Tohoku)
Linear processes in unsteady stably stratified turbulence with mean
shear
15.50-16.30 Tea & Posters
16.30-16.50 M Tanahashi (Tokyo Institute of Technology)
Statistics of coherent fine scale eddies in turbulent channel flows
16.50-17.10 P Flohr (Cambridge)
Self-similar spiral streamlines & local flow alignment in DNS
turbulence
17.10-18.00 General Discussion
09.00-09.45 Y Couder (Ecole Normale Superieure)
The interaction between stretching & rotation : from the laminary
to the turbulent situations
09.45-10.30 F Hussain (Houston)
Core dynamics instability of a vortex in shear: a physical-space
cascade
mechanism
10.30-10.50 C Lee (Tsinghua)
Flow structures in transitional & turbulent flat plate boundary
layers: measurement & visualization
10.50-11.30 Coffee & Posters
11.30-12.15 C Williamson (Cornell)
Fundamental instabilities in spatially - developing & temporally
- developing vortex pairs
12.15-12.35 T Leweke (IRPHE)
Experimental study of elementary vortex interactions: reconnection
&
merging
12.35-14.00 Lunch
14.00-14.45 C Cambon (LMFU at ECL)
Stability of vortex structures in a rotating frame
14.45-15.30 S Le Dizes (IRPHE)
Structure & stability of a new family of non-axisymmetric vortex
solutions
15.30-15.50 A Maurel (LOA - ESPCI)
Dynamical investigation of a vortex using time-reversal mirrors
15.50-16.30 Tea & Posters
16.30-16.50 F Bottausci (LPMMH - ESPCI)
Experimental study of stretched vortices
16.50-17.10 P Petitjeans (LPMMH - ESPCI)
Experimental study of vortices created by a 'double rotating suction'
system
17.10-18.00 General Discussion
09.00-09.45 T Perry (Melbourne)
Structure based modelling for turbulent boundary layers
09.45-10.30 JF Morrison (Imperial)
Structure & energy transfer in wall-bounded turbulence
10.30-10.50 R Nagaosa (National Institute for Resorces &
Environment)
Dynamics of vortex layers and tubes in free-surface & near-wall
turbulent shear flow
10.50-11.30 Coffee & Posters
11.30-12.15 M Lesieur (Institut de Mecanique de Grenoble)
LES & vortex topology in shear & rotating flows
12.15-12.35 K Horiuti (Tokyo Institute of Technology)
Subgrid-scale energy transfer & vortex sheet/tube structures in
turbulence
12.35-14.00 Lunch
14.00-14.45 A Leonard (California Institute of Technology)
Evolution of localized packets of vorticity in turbulence
14.45-15.30 J Hunt (Cambridge)
Vortex dynamics of coherent structures
15.30-15.50 E Fedorovich (Karlsruhe)
Turbulence structure variation in a horizontally evolving convective
boundary layer capped by a temperature inversion
15.50-16.30 Tea & Posters
16.30-16.50 D Drikakis (UMIST)
Extraction of coherent structures & modelling of coherent stresses
in turbulent flows
16.50-17.10 M Stanislas (Ecole Centrale de Lille)
Experimental study of near wall turbulence using particle image
velocimetry
17.10-18.00 General Discussion
19.30- Conference Dinner, Clare College
09.00-09.45 WD McComb (Edinburgh)
Conditional mode elimination with asymptotic freedom for isotropic
turbulence
at large Reynolds numbers
09.45-10.30 K Ohkitani (Kyoto)
Comparison of vorticity & passive vectors in viscous & inviscid
flows
10.30-10.50 X He (Warwick)
A probabilistic method for vortex motion in 2d turbulence
10.50-11.30 Coffee & Posters
11.30-11.50 D Samuels (Newcastle)
Topology of evolving vortex filament tangles
11.50-12.10 W Devenport (Virginia)
Characteristic eddy decompositions in real & model turbulent wakes
12.30-14.00 Lunch
14.00- Final Discussion