scholarly journals Experimental results on frost as a first wall shielding concept for inertial confinement fusion

1990 ◽  
Author(s):  
H. H. Neely ◽  
N. J. Hoffman ◽  
K. A. Murray
Keyword(s):  
Inertial Confinement Fusion ◽  
Experimental Results ◽  
Inertial Confinement ◽  
First Wall ◽  
Confinement Fusion

W and B4C Coatings for Nuclear Fusion Reactors

1998 ◽  
Author(s):  
A. Cavasin ◽  
T. Brzezinski ◽  
S. Grenier ◽  
M. Smagorinski ◽  
P. Tsantrizos
Keyword(s):  
Inertial Confinement Fusion ◽  
Nuclear Fusion ◽  
Energy Levels ◽  
High Hardness ◽  
Fusion Reactors ◽  
Inertial Confinement ◽  
X Rays ◽  
First Wall ◽  
Term Operation ◽  
Confinement Fusion

Abstract The development of nuclear fusion reactors is presently considered to be the only possible answer to the world's increasing demand for energy, while respecting the environment. Nuclear fusion devices may be broadly divided into two main groups with distinctively different characteristics: magnetic confinement fusion (MCF) and inertial confinement fusion (ICF) reactors. Although the two nuclear fusion technologies show similarities in energy levels (as high as 3 J/cm2) and type of environment (high temperature plasmas) to be contained, the materials of choice for the protective shields (first wall in the ICF and deflectors in the MCF) differ significantly. In ICF reactors, multiple laser beams are used to ignite the fuel in single pulses. This process exposes the first wall to microshrapnel, unconverted light, x-rays, and neutrons. B4C is a low Z material that offers high depth x-ray absorption to minimize surface heating, is not activated by neutrons (will not become radioactive), and offers high hardness and vapour temperature. The long term operation envisioned within MCF reactors, where a continuous nuclear fusion of the fuel is sustained within the confinement of a magnetic field, favours the use of high Z materials, such as W, to protect the plasma exposed deflectors. The reason is a lower erosion rate and a shorter ionization distance in the plasma, which favours the redeposition of the sputtered atoms, both resulting in a lower contamination of the plasma. The production of the first wall and the deflector shields using solid B,C and W materials respectively, is obviously unthinkable. However, ProTeC has developed high density coatings for both ICF and MCF nuclear fusion reactors. W coatings with less then 2% porosity have been produced for both, the Tokamac MCF reactor and its Toroid Fueler. The toroid fueler is a plasma generating device designed to accelerate particles and inject them into the centre of the operating fusion reactor in order to refuel. For the application in an ICF reactor, B4C coatings exhibiting porosity levels below 3% with a hardness above 2500 HV have been deposited directly onto Al substrate. Properties such as outgassing, resistance to erosion and shrapnel, and the influence of x-rays have been studied and showed exceptional results.

scholarly journals Parametric design study of a nuclear-pumped laser-driven inertial confinement fusion power plant

1993 ◽  
Vol 11 (3) ◽  
pp. 537-548 ◽  
Author(s):  
Denis E. Beller ◽  
John M. Jacobson ◽  
George H. Miley ◽  
Maria Petra ◽  
Yasser Shaban
Keyword(s):  
Inertial Confinement Fusion ◽  
Power Reactor ◽  
Large Fraction ◽  
Coupling Efficiency ◽  
Inertial Confinement ◽  
First Wall ◽  
Design Study ◽  
Natural Geometry ◽  
Confinement Fusion ◽  
Fusion Yield

In an earlier preliminary design study, we proposed a novel nuclear-pumped laser-driven (NPL) inertial confinement fusion (ICF) power reactor that represents an important variation on the “neutron feedback” concept for ICF. This NPL-driven ICF concept also included an advanced, DT-seeded, D3He-fueled pellet and magnetic protection of the first wall of the reactor chamber. Advantages that were demonstrated for this approach included increased efficiency for laser-to-target energy coupling, increased efficiency for thermalto-electric energy conversion, and reduced neutron activation and waste. The coupling efficiency is enhanced because a nuclear-pumped flashlamp is directly pumped by fission fragments from uranium micropellets within the lamp medium. The thermal conversion efficiency is greater because a large fraction of the ICF pellet&s fusion yield is in charged Finally, the fraction of the fusion yield carried by neutrons is significantly reduced in comparison with pure D-T-fueled pellets; thus, neutron-induced activity in the first wall is decreased and safety is increased. The initial study indicated these factors could result in a required driver energy of 5 MJ (vice 10 MJ currently projected) and a pellet gain of only 50 (vice 100 currently projected) for a feasible l,000-MWe power reactor operating with approximately six pellets per second. The current study includes a refined analysis of an NPL-driven ICF power reactor of this type. A cylindrical design for the fission/NPL blanket is selected as a “natural” geometry for pumping the NPL. Required enrichments and criticalities are then predicted for the multiplication of the fusion neutron yield needed to pump the NPL. Based upon these results, we report a more detailed parametric study of the efficiencies for converting neutron, X-ray, and plasma yields from advanced ICF pellets into electrical and optical energy flows required in this concept. We also examined breeding tritium in a lithium blanket layer. Results from these studies help define topics and parameter spaces for further research on this unique reactor concept.

scholarly journals Quantitative observation of monochromatic X-rays emitted from implosion hotspot in high spatial resolution in inertial confinement fusion

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Kuan Ren ◽  
Junfeng Wu ◽  
Jianjun Dong ◽  
Yaran Li ◽  
Tianxuan Huang ◽  
...  
Keyword(s):  
Spatial Resolution ◽  
Inertial Confinement Fusion ◽  
High Spatial Resolution ◽  
Theoretical Calculations ◽  
Photon Number ◽  
Experimental Results ◽  
Inertial Confinement ◽  
X Rays ◽  
Gaussian Source ◽  
Confinement Fusion

AbstractIn inertial confinement fusion, quantitative and high-spatial resolution ($$< 10\,\upmu $$ < 10 μ m) measurements of the X-rays self-emitted by the hotspot are critical for studying the physical processes of the implosion stagnation stage. Herein, the 8 ± 0.39-keV monochromatic X-ray distribution from the entire hotspot is quantitatively observed in 5-$$\upmu $$ μ m spatial resolution using a Kirkpatrick–Baez microscope, with impacts from the responses of the diagnosis system removed, for the first time, in implosion experiments at the 100 kJ laser facility in China. Two-dimensional calculations along with 2.5% P2 drive asymmetry and 0.3 ablator self-emission are congruent with the experimental results, especially for the photon number distribution, hotspot profile, and neutron yield. Theoretical calculations enabled a better understanding of the experimental results. Furthermore, the origins of the 17.81% contour profile of the deuterium-deuterium hotspot and the accurate Gaussian source approximation of the core emission area in the implosion capsule are clarified in detail. This work is significant for quantitatively exploring the physical conditions of the hotspot and updating the theoretical model of capsule implosion.

scholarly journals Time-dependent measurement of high-power laser light reflection by low-Z foam plasma

2021 ◽  
Vol 9 ◽  
Author(s):  
M. Cipriani ◽  
S. Yu. Gus’kov ◽  
F. Consoli ◽  
R. De Angelis ◽  
A. A. Rupasov ◽  
...  
Keyword(s):  
Inertial Confinement Fusion ◽  
Diagnostic Techniques ◽  
Experimental Results ◽  
Time Dependent ◽  
Light Reflection ◽  
Inertial Confinement ◽  
Solid Media ◽  
Dependent Measurement ◽  
Laser Produced Plasma ◽  
Confinement Fusion

Abstract Porous materials have many applications for laser–matter interaction experiments related to inertial confinement fusion. Obtaining new knowledge about the properties of the laser-produced plasma of porous media is a challenging task. In this work, we report, for the first time to the best of our knowledge, the time-dependent measurement of the reflected light of a terawatt laser pulse from the laser-produced plasma of low-Z foam material of overcritical density. The experiments have been performed with the ABC laser, with targets constituted by foam of overcritical density and by solid media of the same chemical composition. We implemented in the MULTI-FM code a model for the light reflection to reproduce and interpret the experimental results. Using the simulations together with the experimental results, we indicate a criterion for estimating the homogenization time of the laser-produced plasma, whose measurement is challenging with direct diagnostic techniques and still not achieved.

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