Inertial Fusion Energy Materials under Irradiation

Transcription

1 Inertial Fusion Energy Materials under Irradiation Technology watch workshop on IFE-KiT 22 March, 2010 (11:30-18:30) hosted by Instituto Fusion Nuclear Universidad Politecnica de Madrid (ETSII) J. M. Perlado

2 Inertial Confinement Fusion: Reactor concepts and NIF MATERIALS assessment HYLIFE-II Type of Facility: Ignition, Reactor/Protection Structural Material : Steel SS304 Lifetime = that of the plant Flibe: Coolant, T reproduction, and protection MATERIALS Target composition (nanostructures) First Wall, Optics Structural, Coolant Activation and Damage Heat Deposition, T economy Effects of: NIF SOMBRERO HiPER Neutron Debris Shrapnel X-rays; High T; High P

3 MATERIALS FOR TARGETS

4 First results on shockwave generation and propagation on Ta: Pictures show the resulting crystal structure (5 millions of atoms) after 5ps MD. Shock propagates in direction [100]. Advanced Materials NANOCRYSTAL METALLIC FOAMS Advance Manufacturing Techniques in Nano Microtechnology Piston velocities were in the range from 180 Km/s to 720 Km/s. Sample compression reaches bars.

5 CENTRAL IGNITION DIRECT DRIVE INDIRECT DRIVE X- Rays Neutrons Ions Energy -Direct. Drive -Indirect Drive 1,5% 18% 75% 75% 23% 7% OPERATIONAL WINDOWS FOR DRY-WALL AND WETTED-WALL IFE CHAMBERS

6 Spectra for NRL Spectra for HY DD X ray spectra Spectra for ID

7 SHOCK IGNITION We don t have tables!! I asked John!

8 Neutron Spectra High gain capsule with <> 2x neutrons / pulse 1.00E E-01 constant density in target high and low density distinction Probability 1.00E E E E E E E E E E E E E E E E E+02 MeV

9 Assuming 4 m Radius Wall after protection = 1 cm of Fe DAMAGE RATE MonteCarlo detailed calculations

10 Designing systems by simulation of the time-dependent neutron intensities and energy spectra is already well done with existing methodology. This is an example assuming first wall protection (which will be not needed for HiPER operation except experiments in mock-up testing cells could be approved)

11 NEUTRONICS 3D DETAILED CALCULATIONS USING CAD AND MCNPX. It is time to start to use in Inertial Fusion Reactors Concepts and Facilities to get consequences such as Activation / Damage.defining structures and materials

12 NEUTRON TRANSPORT CALCULATION HYLIFE-II 1,0E+12 Flux Density TART Spectrum, flux intensity, and average neutron energy in the FSW with 60 cm of Flibe thickness and 2240 MW fusion power Flux Density (n*cm -2 s -1 MeV -1 ) 1,0E+11 1,0E+10 1,0E+09 1,0E+08 1,0E+07 1,0E+06 %DIF ENDFB6.0 %DIF ENDFB6.8 %DIF JENDL3.2 %DIF JEFF %DIF= (TART-MCNP)/TART*100 1,0E ,0E+04 1,0E-05 1,0E-04 1,0E-03 1,0E-02 1,0E-01 1,0E+00 1,0E+01 1,0E+02 Energy (MeV) TART2000 MCNP4c2 ENDF/B-VI.0 ENDF/B-VI.8 JENDL3.3 JEFF-3.1 φ (n cm -2 s -1 ) 5.30E E E E E+14 <E> (MeV) 3.06E E E E E

13 Selection of Low Activation elements in HYLIFE-II irradiation conditions Limits in the concentration (weight fraction) for all natural elements DOMINANTS NUCLIDES LIMIT CONCENTRATION RECYCLING RECYCLING ELEMENT SLB REMOTE HANDS-ON SLB REMOTE HANDS-ON NB NB 94 (100.) NB 94 (100.) NB 94 (100.) 6,93E-07 1,91E-05 4,78E-08 TB H0166M (100.) H0166M (100.) H0166M (100.) 4,82E-06 1,43E-04 3,67E-07 ZN - CO 60 (100.) - NL 7,59E-01 NL Acceptability of pure elements under Shallow Land Burial Criteria (SLB) NO limit % 1-10% 0,1-1% 0,1-1 ppm ppm ppm 1-10 ppm Elements with good engineering properties but not acceptable from m activation Elements as impurities restricted to very severe limits

14 Average X-ray energy 8,8 kev Energy Spectra Burning hydrodynamic codes are used to calculate the energy spectra. IN THESE CALCULATONS: Shock target of 48 MJ (J. Perkins). SO CRITICAL TARGET COMPOSITION!!! REQUIREMENTS FOR TARGET AREA REPETITIVE Particles go up to some MeVs

15 HOW X-RAYS AND IONS ARRIVE TO FIRST WALL TIME DEPENDENT Time distribution of fluence on wall (every 200 ns) Physical - Nuclear (up to MJ) and electronic (MJ onwards). It can be studied with SRIM software. MUCH MORE FUNDAMENTAL WORK IS NEEDED!!! Chemical - Reactions on surface (not in Tungsten, very important in carbon containing walls) Radiation enhanced sputtering Diffusion of interstitial atoms that diffuse to the surface and sublimate (important in carbon)

16 Origin Clusters, Debris, Shrapnel Produced during the ablation of the target, and ulterior reemission processes from the chamber itself Energy and size distribution not available (but for some experiments) Particles in the nano-scale (clusters) Sputtering of polyatomic species and clusters is one/two orders of magnitude higher. No models available. Their effect has to be studied for every specific case. Particles in the micro-scale (debris) They appear as deposits/small particles/droplets Damage up to some microns (crater/erosion) Particles in the tens of micrometer-scale (Shrapnel) They appear as big fragments Damage of some hundreds of microns (crater/erosion) Their effect can be modelled using Hypervelocity Impact simulations (Autodyn)

17 Energy deposition Simulation of the spatio-temporal deposition of energy FLUKA, MCNPX Thermo-mechanical effects ANSYS (As first approx. we do not accept melting/evaporation of wall) WHEN PROTECTION OR PHASE TRANSITION: FLUENT, CFX X-ray damage A massive photoelectric effect on surface is expected. Damage? (roughly 5% of X-rays will result in the emission of e -, i.e. 2 x e -.m -2 ) Ion damage Sputtering SRIM code. The design of target is critical (a 2 mm radius target with 35μm thick plastic surface contains about 2 orders of magnitude more atoms than a monolayer of the 5 m radius tungsten wall; sputtering efficiency of C atoms 1-10%) Defects resulting in modifications (hardness, corrosion, fracture...). Is there software to simulate those effects available? Debris/Shrapnel Simulation of debris/shrapnel formation Simulation of damage on wall (micrometeorite impact theory) ANSYS

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19 Thermomechanical simulation for the first wall In all the cases studied thermal stress is very far from yield stress, but temperature could be close to melting point (~3695 K) if Pulse energy is higher than 2 J/cm2. Pulse Energy (J/cm2) Temperature(K) Stress (MPa) >

20 In the case of Tungsten and for average kinetic energy particles Ion Number of particles Average energy (kev) Sputtering (at/ion) Tungsten Shots to remove monolayer (Tungsten 1,8E16 atoms/cm2) (5 m radius chamber) H 1,18E D 1,05E20 191, T 9,45E He 1,9E % 1e7 4He 1,7E C 1,38E % 2,7e4 13C 1,15E % 1,3e6

21 We have these inputs data, we could get responses with DEPENDENCE OF PROTECTION Temperature (ev) Energy (J) Time (s) Time (s)

22 Incoming laser is first deflected and focused in the final optics Chamber wall positioned radially between target and optics with penetrations to allow the entry Mirror Lens Pinhole Disposable Lens 8 m 5 m High energy neutrons X-Rays Chamber black body like radiation Ion debris 8 m 16 m

23 Integrated energy deposition Energy contributions orders of magnitude lower than the energy coming from the laser (~2KJ) Big uncertainties in photons but we can still get a taste Local hot spots could appear

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25 Identification of defects and production under irradiation with / without H. It is absolutely clear that in both kind of defects, the number of defects, both without H atoms and with H atoms, increases with increasing PKA energy.

26 Structural Materials under Irradiation (Neutrons) = FULL COOPERATIVE WORK IN MODELLING AND EXPERIMENTS BETWEEN EFDA AND IFE GROUPS MATERIALS Ceramics (Windows/Optics): SiO 2, Alumina, FCa First Wall: Be, C, W, Ferritic Steels Structural: Ferritic Steels (FeCr based), Vanadium Alloys, Composites based in SiC or C fibers. Nanocrystal material for high T / high P conditions in target design, and through Oxide Dispersion Strength in FeCr Ferritic Steels.

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28 The Grand Challenge: predict strain localization and work hardening in irradiated tensile tests TEM weak beam Stress-strain relation of tensile specimens of irradiated Cu (from: M. Victoria et al. 2001) We now have a mesoscale computational tool to study these problems: Strain hardening beyond the formation of channels Simulation of irradiated copper tensile specimen We will extract DD-based constitutive laws for material models in FE calculations

29 SiC J.M. Perlado, L. Malerba, T. Díaz de la Rubia, Fusion Technology, 34, no. 3, part 2 (1998) Molecular Dynamics: Macroscopic Application Defining Stress-Strain Strain curve

30 Experimental methodology in FeCr for EFDA Materials: Alloys prepared from 99,99 Fe and Cr by arc melting in a pure Ar atmosphere. Nominal concentrations: 1, 2, 3, 5, 7, 10, 12 y 15% at Cr. Effect of Cr content Ion irradiation conditions Irradiations performed in the AIM facility of the Forschungszentrum Dresden-Rossendorf (FZD)*: Fe kev Dose: 2x10 18 ions/m 2 (~0.8 dpa) Flux: 2x10 15 ions/m 2 s Temperatures: 140K and 300K TEM observation at RT JEOL 200 kev Irradiation Temperature Irradiation time 300 K 140 K Observation time

31 Computational KMC model Clusters > 100 defectos ( >2 nm) The comparison with experiment is not still correct but is gping with less uncertainty to fox such results

32 Radiation Damage in Repetitive Systems There will be consequences in behavior (?) Microscopic simulation on defect generation at low doses. Good starting.. NOT ENOUGH

33 Generation of Radiations and Beams by High Power laser Ultraintense short pulse laser Gas-cluster target Laser implosion Neutron, Protons X-rays Merit : low debris and high rep-rate small laser energy Demerit: low efficiency Merit: high efficiency Demerit: high energy neutron High energy laser 超高エネルギー密度プラズマの発生と精密計測 ペタワットレーザー QuickTimeý Dz êlí ÉvÉçÉOÉâÉÄ Ç Ç±ÇÃÉsÉNÉ`ÉÉǾå ÇÈÇžÇ½Ç ÇÕïKóvÇ-Ç Solid film target Merit: high efficiency Demerit: debris X-ray MeV ion Neutron MeV electron μ-on Positron Hard X-ray γ ray MeV 電子 MeV イオン 中性子 中間子 陽電子 D+D: 2.4 MeV neutron D+T: 14 MeV neutron D+ 3 He: 14Mev Proton 実験計測

34 Neutron production Scaling depending on laser energy Fast ignition FIREX Q=1 (DT) NIF Central ignition Neutron yield/pulse fs Falcon Exploding pusher 7 Li(p,n) 7 Be E fs JanUSP nat Pb(p,xn)Bi g-d2 LHART VULCAN 11 B(p,n) 11 C Implosion Cluster CD shell Nuclear reaction Expected by laser fusion Laser pulse energy (J)

35 Various neutron production processes and energy efficiency Type of nuclear reactions generation efficiency Neutron/ particle Energy cost MeV/neutron 235 U(n,f) 1n/fission 180 DT fusion 1n/fusion - D-Be (Ed = 15MeV) 1.2x 10-2 n/d 1,200 P-Be ( Ep =5MeV) 10-4 n/p? 50,000 Li-P ( Ep = 3MeV) 10-4 n/p 30,000 Electron beam (E e =35MeV) 1.7x10-2 n/e 2,000 Hg sparation (Ep = 3GeV) 75 n/p 35

36 Thanks for your attention and. coming to Madrid!!!!!!!!!!!!!!!!!

37 IFE REACTORS DESIGNS MAIN THREATS TO THE CHAMBER WALL -High temperatures -> evaporation -Ion implantation (in particular He) -Sputtering, ablation -Mechanical damage (roughening, embrittlement, ) -Neutrons

38 We have / will need to develop an updated methodology for IFE accident analyses In order to maximize the S&E advantages of IFE, accident consequences must be addressed realistically In early studies, safety analysis tools were not very refined which often resulted in overly conservative safety analyses and safety-important design details were not available to incorporate into the safety assessment We have adopted and adapted computer codes traditionally used by MFE, and integrated them in a set of state-of-the-art codes/libraries for IFE safety analyses These tools have provided the first self-consistent analysis to understand the integrated behavior of an IFE chamber under accident conditions We have applied this methodology to various IFE designs and a target fabrication facility, with the goal of demonstrating that fusion designs could meet the noevacuation objective (1 rem) HYLIFE-II SOMBRERO

39 = input file = FORTRAN code = Data library = Output data TART input for γ-ray transport SET OF COMPUTER CODES AND LIBRARIES TART/MCNP input: model geometry, materials TART: photon/ neutron transport TARTREAD ACAB input: irradiation history, neutron flux, materials, output options ACAB: activation calculations Radioactive inventory, afterheat, etc TARTCHECK: verification of TART geometry Photon/neutron energy deposition, path-lengths ENDL: cross-section library FENDL/A-2.0: cross-section library FENDL/D-2.0: decay library CHEMCON input: geometry, energy source term CHEMCON: heat transfer Time-temperature history MELCOR input: geometry, radioactive source term MELCOR: thermal-hydraulics Radioactivity release fraction DCF library OFF-SITE DOSES 39

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