The role of Academia
Conference
30TH SEPTEMBER – 1ST OCTOBER, 2015 PORT OF DOVER
Alexei Sentchev, PhD Laboratory of Oceanography & Geosciences, Wimereux, France
Laboratory of Oceanography & GeosciencesUMR 8187 LOG (CNRS - UL1 - ULCO)
htpp://log.univ-littoral.fr
Oceanographic vessel Sepia II (INSU)
Zodiac
Lab rooms
Cytometer
Thermostated rooms
Chemical analyses (CHN, HPLC…)
Many different sensors for in situ physico-chemical measurements (velocimeters, oxygen, pH, temperature, salinity, PAR, swell, fluorometers…)
Numeric cameras, High speed camera
MInversed microscope
Epifluorescence microscope
Scanning Electron Microscopy (SEM)
Optic grape
ROV
Facilities
Igor Kourchatov Vagn Walfrid Ekman
Academia - Industry partnership… and the Progress
Turbine test in wind tunnel is not sufficient
Geophysical flow dynamics is 3-dimensional:- Variation in wind speed coupled with variation in direction causes hard damage- Re nb increases along with the device size: more load – more fatigue – more damage
Wind industry
Significant increase of damage is observed as the size of wind turbines increases
Resource characterization in the Iroise Sea (W.Brittany)
Two HF radars operating at 12.4 MHz since July 2006.
Resolution: 1.5 km along beam, 2° angular, 20 min temporal resolution
Velocity times series available since 04/2007 (corrected for sea state)
Iroise Sea and radar coverage zone
Surface currents measured by the radar during a tidal cycle
Radial velocities from 2 radars are combined to form current vectors
Remote sensing of currents by HF radars– continuously operating system – velocity measurements over a large area, in the surface layer (not so critical for barotropic tidal flow)– provides all major metrics of a flow
Transmitting/Receiving antenna arrays
Bragg peak shift provides radial velocity estimate of the current
U = f r/2
Principle of velocity measurements
Bragg peaks in backscattered energy spectra
Direction finding (MUSIC) provides high resolution radial velocity maps
BEAM FORMING DIRECTION FINDING
Variational interpolation (2dVar) - performs gap filling, smoothing,- provides velocity vector maps, curl v, div v & error estimates
10° x 1.5 km 2° x 1.5 km
Pb: gappy data
Radar data processingRo
utine
ly u
sed
more realistic
Probability density of velocity
Loc. B Fromveur Strait
Loc. A NW of the Ushant Is.
Tidal flow characterization
12°
3°43°
Δθ = | θ flood - θ ebb – 180° |
Asymmetry of current velocity and direction
0.5 < a < 2.5
Neap
a = <Vflood>/<Vebb>
HFR velocities vs ADCP velocity profiles
Location C <V(avg)/V(sur)>
Mean Err (%)
NW Ushant 0.82 0.83 4
Fromveur 0.86 0.78 3
Velocity time series in the Fromveur St.
ADCP vel profile approximation
V(z)=V0 (z/d)1/α
Fromveur: α = 5.8 (ebb/flood flow)NW Ushant:
α = 6.5 (flood flow) α = 6.9 (ebb flow)
Off-shore location
good location
Power density: overall mean estimates
kW/m2
NW U
Fro
mv
best location Surface layerMaximum P: 20 kW/m2
annual mean > 1.5 kW/m2Bottom layer: 3 times lower
Power density: maximum (color shading) annual mean (white
contour) Fromveur: P variations during a day & a month
Resource assessment in Raz BlanchardChannel Isles region
Tidal turbine farm
Recommendations and concluding remarks
Partnership with Academia is a good way for saving money
It offers solution to many issues
Academia is looking for applications (sharing the knowledge and technology)
There are many highly qualified people motivated for cooperation and joint activities
(we want to maintain traditions of Tesla, Kourchatov and many others …)
If you are looking for a partnership, visit our web site: log.univ-littoral.fr