Report on the French activities on dust Grisolia with help of Arnas (PIIM), Coeudel (PIIM), Roche (IRFM), Onofri (IUSTI), Barbosa (IUSTI), Vrel (LSPM), Delaporte (LP3), Gensdarmes (IRSN)
outline Current activities : W dust production in dusty plasma laboratory (Arnas, Couedel, PIIM, Marseille) Dust measurements : The Tore Supra electrostatic detector (Roche, IRFM) Dust suspension in Tore Supra (Gendarmes, IRSN) Dust suspension measurements with Light Extinction Spectrometry (Onofri, Barbosa, IUSTI, Marseille) Others activities: Dust production by milling (Vrel, LSPM, Paris) and laser interaction with material (Delaporte, LP3, Marseille) Toxicology studies (Menard, DSV, Marcoule) Dust suspension studies in the BISE setup (Gensdarmes, IRSN) Planned activities for 2012 and following
W dust production in dusty plasma laboratory (Arnas, Couedel, PIIM, Marseille) DC glow discharge L. Couëdel, K. Kalathiparambil and C.Arnas Laboratoire PIIM, Aix-Marseille Univ/CNRS, Marseille, France Ar = 0.6 mbar V D ~ - 600 V P ~ 3 kw/m² n e = 2 10 16 m -3 T e = 2 ev Tungsten flux ~ 2 10 18 m -2.s -1 Sputtering yield ~ 4% 1 : Tungsten cathode 3 : Substrate holder 2 : Grounded anode 4 : Window
W dust production in dusty plasma laboratory (Arnas, Couedel, PIIM, Marseille) Electron microscopy images of tungsten dust particles SEM, discharge duration: 60s Ar = 0.6 mbar I D = 40 ma TEM, discharge duration: 60s Tungsten nanocrystallites SEM, discharge duration: 300s Conclusions: fractal particles of increasing size with time. Same with N2 plasma?
The Tore Supra electrostatic detector
The Tore Supra electrostatic detector
The Tore Supra electrostatic detector
The Tore Supra electrostatic detector
Dust suspension in Tore Supra
Dust suspension in Tore Supra No dust collected
Dust suspension in Tore Supra
Dust suspension in Tore Supra
Dust suspension in Tore Supra Conclusion : Preliminary results convincing much more studies to get the ratio of dust put in suspension
Dust suspension measurements with Light Extinction Spectrometry Le LES laboratory experiment
Dust suspension measurements with Light Extinction Spectrometry SEM of SkySpring powder recovered when gas flow is stopped Suspensions of tungsten nanopowders supplied by SkySpring, Inc. (nominal dry powder : D=1-200nm, spherical),
Dust suspension measurements with Light Extinction Spectrometry Df (fractal dimension)=2,7 np, rp = number and mean radius of primary particles Rg = radius of gyration of aggregate Kf=1,593 No effect of wall proximity, no effect of plasma plume as observed in shock wave in gas Conclusion: LES is very promising if some dust information is available as the fractal dimension
Dust production by milling and laser interaction with material Objectives = to produce dust (ITER relevant) to undertake several studies as toxicology or dust suspension (lab) Planetary milling (Vrel, LSPM) Laser production (Delaporte, LP3) Jars and balls movement during planetary ball milling; by choosing w = -2W, the ball will shock the jar perpendicularly Up to now, quantities but no good shape Work in 2012: dust production of 100-150nm Tungsten particles collected in tokamaks (left) and formed during laser ablation (right). Small quantities but good shape
Toxicology studies (Mallard, CEA DSV) Tritiated or deuterated dust injection The epithelium (MucilAir ) expresses organ-specific structures (cilia) and functions, including defence mechanisms (mucus production and cilia beating), similarly to the in vivo airway epithelia. MucilAir has the ability to synthesize and release inflammatory mediators. Deuteration by plasma interaction on dust (to be tested) or by laser ablation of a deuterium implanted target Tritiation by gas implantation at CEA Studies on the W toxicity + deuterium or tritium diffusion from dust to cells and to the nutritive Solution (starting 2012, financed by CEA internal project)
Dust suspension in the BISE setup (Gensdarmes, IRSN)
Dust suspension in the BISE setup (Gensdarmes, IRSN) Dust from scraping of the Tore Supra limiter
Dust suspension in the BISE setup (Gensdarmes, IRSN) Work in 2012: dust suspension with W from milling and laser (? Quantity) with C from TS
Conclusions W dust production in dusty plasma laboratory (Arnas, Couedel, PIIM, Marseille) (continued) Dust measurements : The Tore Supra electrostatic detector (Roche, IRFM) (continued if ITER relevant) Dust suspension in Tore Supra (Gendarmes, IRSN) (continued) Dust suspension measurements with Light Extinction Spectrometry (Onofri, Barbosa, IUSTI, Marseille) (continued but out fusion business?) Others activities: Dust production by milling (Vrel, LSPM, Paris) and laser interaction with material (Delaporte, LP3, Marseille) (continued) Toxicology studies (Menard, DSV, Marcoule) (starting) Dust suspension studies in the BISE setup (Gensdarmes, IRSN) (starting) Tritiated dust studies (starting) New activities: Tritiated JET dust characterization (if CEA proposal accepted by IO) Dust injection in Tore Supra for operation studies Dust injector from dusty plasma community Several topics considered : disruption studies, dust for SOL characterization, dust collection in the SOL Dust cleaning system Laser dust suspension at low pressure or shock wave at atm. pressure: already studied (Industrial support needed)
Runaway electrons and dust production : Conclusions Tore Supra important activity: experimental study and model of the runaway production Dust production will be studied as well!