Proposal of a Novel Blanket System Using LiF-BeF2-LiI for a Fusion Reactor

2013 ◽  
Author(s):  
Hiroki Shishido ◽  
Youngmin Han ◽  
Kentaro Matsui ◽  
Noritaka Yusa ◽  
Hidetoshi Hashizume
Keyword(s):  
Monte Carlo ◽  
Melting Point ◽  
Numerical Simulations ◽  
Molten Salt ◽  
Fusion Reactor ◽  
Experimental Results ◽  
Molar Ratio ◽  
Data Library ◽  
Measured Density

This study proposes LiF-BeF2-LiI as a molten salt for a liquid blanket system of a fusion reactor. Firstly, the melting point of LiF-BeF2-LiI is measured as a function of the molar ratio of LiI. The experimental results confirmed that the melting point decreases to 398.2 °C when LiF:BeF2:LiI = 19:9.5:71.5, which is consistent with an earlier report. Experiments to evaluate the density and viscosity of LiF-BeF2-LiI are also carried out. The experiments revealed that the density of LiF-BeF2-LiI increases with the molar ratio of LiI, and the viscosity of LiF-BeF2-LiI (LiF:BeF2:LiI = 2:1:1) is somewhat larger than that of LiF-BeF2 (LiF:BeF2 = 2:1) but much smaller than that of LiF-BeF2 (LiF:BeF2 = 3:2). Monte Carlo numerical simulations using MVP-2.0 with JENDL-4.0 data library are conducted on the basis of the measured density to discuss the feasibility of a blanket system using LiF-BeF2-LiI. The numerical simulations demonstrate that LiF-BeF2-LiI can realize TBR>1.4, which is required for a fusion blanket system, with Be pebble layer and enriching 6Li.

STUDY OF THE GRAIN BOUNDARY MIGRATION IN A TRICRISTAL PURE ICE WITH BUBBLES

Anales AFA ◽  
2019 ◽  
Vol 30 (3) ◽  
pp. 47-51
Author(s):  
P.I. Achával ◽  
C. L. Di Prinzio
Keyword(s):  
Monte Carlo ◽  
Grain Boundary ◽  
Numerical Simulations ◽  
Triple Junction ◽  
Boundary Migration ◽  
Optical Microscope ◽  
Physical Parameters ◽  
Grain Boundary Migration

In this paper the migration of a grain triple junction in apure ice sample with bubbles at -5°C was studied for almost 3hs. This allowed tracking the progress of the Grain Boundary (BG) and its interaction with the bubbles. The evolution of the grain triple junction was recorded from successive photographs obtained witha LEICA® optical microscope. Simultaneously, numerical simulations were carried out using Monte Carlo to obtain some physical parameters characteristic of the BG migration on ice.

A new method for monitoring the redox potential of fuel salt based on the deposition of 95Nb on Hastelloy C276

2021 ◽  
Vol 109 (5) ◽  
pp. 357-365
Author(s):  
Zhiqiang Cheng ◽  
Zhongqi Zhao ◽  
Junxia Geng ◽  
Xiaohe Wang ◽  
Jifeng Hu ◽  
...  
Keyword(s):  
Redox Potential ◽  
Molten Salt ◽  
Specific Activity ◽  
Chemical Reduction ◽  
Quantitative Approach ◽  
Experimental Results ◽  
New Method ◽  
Molten Salt Reactor ◽  
Fuel Salt ◽  
Well Correlation

Abstract To develop the application of 95Nb as an indicator of redox potential for fuel salt in molten salt reactor (MSR), the specific activity of 95Nb in FLiBe salt and its deposition of 95Nb on Hastelloy C276 have been studied. Experimental results indicated that the amount of 95Nb deposited on Hastelloy C276 resulted from its chemical reduction exhibited a positive correlation with the decrease of 95Nb activity in FLiBe salt and the relative deposition coefficient of 95Nb to 103Ru appeared a well correlation with 95Nb activity in FLiBe salt. Both correlations implied that the measurement of 95Nb activity deposited on Hastelloy C276 specimen might provide a quantitative approach for monitoring the redox potential of fuel salt in MSR.

scholarly journals Statistical Analysis of Tritium Breeding Ratio Deviations in the DEMO Due to Nuclear Data Uncertainties

2021 ◽  
Vol 11 (11) ◽  
pp. 5234
Author(s):  
Jin Hun Park ◽  
Pavel Pereslavtsev ◽  
Alexandre Konobeev ◽  
Christian Wegmann
Keyword(s):  
Monte Carlo ◽  
Fusion Reactor ◽  
Nuclear Data ◽  
Data File ◽  
Nuclear Model ◽  
Model Parameters ◽  
Tritium Breeding ◽  
Tritium Breeding Ratio ◽  
Nuclear Data Library ◽  
Breeding Ratio

For the stable and self-sufficient functioning of the DEMO fusion reactor, one of the most important parameters that must be demonstrated is the Tritium Breeding Ratio (TBR). The reliable assessment of the TBR with safety margins is a matter of fusion reactor viability. The uncertainty of the TBR in the neutronic simulations includes many different aspects such as the uncertainty due to the simplification of the geometry models used, the uncertainty of the reactor layout and the uncertainty introduced due to neutronic calculations. The last one can be reduced by applying high fidelity Monte Carlo simulations for TBR estimations. Nevertheless, these calculations have inherent statistical errors controlled by the number of neutron histories, straightforward for a quantity such as that of TBR underlying errors due to nuclear data uncertainties. In fact, every evaluated nuclear data file involved in the MCNP calculations can be replaced with the set of the random data files representing the particular deviation of the nuclear model parameters, each of them being correct and valid for applications. To account for the uncertainty of the nuclear model parameters introduced in the evaluated data file, a total Monte Carlo (TMC) method can be used to analyze the uncertainty of TBR owing to the nuclear data used for calculations. To this end, two 3D fully heterogeneous geometry models of the helium cooled pebble bed (HCPB) and water cooled lithium lead (WCLL) European DEMOs were utilized for the calculations of the TBR. The TMC calculations were performed, making use of the TENDL-2017 nuclear data library random files with high enough statistics providing a well-resolved Gaussian distribution of the TBR value. The assessment was done for the estimation of the TBR uncertainty due to the nuclear data for entire material compositions and for separate materials: structural, breeder and neutron multipliers. The overall TBR uncertainty for the nuclear data was estimated to be 3~4% for the HCPB and WCLL DEMOs, respectively.

Additive manufacturing of pure copper: From numerical simulations to experimental results

2021 ◽  
Author(s):  
Hagen Kohl ◽  
Lisa Schade ◽  
Gabor Matthäus ◽  
Tobias Ullsperger ◽  
Burak Yürekli ◽  
...  
Keyword(s):  
Additive Manufacturing ◽  
Numerical Simulations ◽  
Pure Copper ◽  
Experimental Results

Effect of Ramp Angle on the Anti-Loosening Ability of Wedge Self-Locking Nuts Under Vibration

2018 ◽  
Vol 140 (7) ◽  
Author(s):  
Jianhua Liu ◽  
Hao Gong ◽  
Xiaoyu Ding
Keyword(s):  
Finite Element ◽  
Numerical Simulations ◽  
Production Technology ◽  
Material Properties ◽  
Threshold Value ◽  
Commercial Production ◽  
Experimental Results ◽  
Fe Method ◽  
Transversal Vibration

Recently, the wedge self-locking nut, a special anti-loosening product, is receiving more attention because of its excellent reliability in preventing loosening failure under vibration conditions. The key characteristic of a wedge self-locking nut is the special wedge ramp at the root of the thread. In this work, the effect of ramp angle on the anti-loosening ability of wedge self-locking nuts was studied systematically based on numerical simulations and experiments. Wedge self-locking nuts with nine ramp angles (10 deg, 15 deg, 20 deg, 25 deg, 30 deg, 35 deg, 40 deg, 45 deg, and 50 deg) were modeled using a finite element (FE) method, and manufactured using commercial production technology. Their anti-loosening abilities under transversal vibration conditions were analyzed based on numerical and experimental results. It was found that there is a threshold value of the initial preload below which the wedge self-locking nuts would lose their anti-loosening ability. This threshold value of initial preload was then proposed for use as a criterion to evaluate the anti-loosening ability of wedge self-locking nuts quantitatively and to determine the optimal ramp angle. Based on this criterion, it was demonstrated, numerically and experimentally, that a 30 deg wedge ramp resulted in the best anti-loosening ability among nine ramp angles studied. The significance of this study is that it provides an effective method to evaluate the anti-loosening ability of wedge self-locking nuts quantitatively, and determined the optimal ramp angle in terms of anti-loosening ability. The proposed method can also be used to optimize other parameters, such as the material properties and other dimensions, to guarantee the best anti-loosening ability of wedge self-locking nuts.

scholarly journals Numerical Simulations of V-Shaped Plates Subjected to Blast Loadings: A Validation Study

2016 ◽  
Vol 10 (11) ◽  
pp. 203
Author(s):  
Mohd Zaid Othman ◽  
Qasim H. Shah ◽  
Muhammad Akram Muhammad Khan ◽  
Tan Kean Sheng ◽  
M. A. Yahaya ◽  
...  
Keyword(s):  
Numerical Simulation ◽  
Numerical Simulations ◽  
Variable Mass ◽  
Blast Loading ◽  
Experimental Results ◽  
Average Difference ◽  
Simulation Results ◽  
Blast Loadings ◽  
Carrier Vehicle ◽  
Good Agreement

A series of numerical simulations utilizing LS-DYNA was performed to determine the mid-point deformations of V-shaped plates due to blast loading. The numerical simulation results were then compared with experimental results from published literature. The V-shaped plate is made of DOMEX 700 and is used underneath an armour personal carrier vehicle as an anti-tank mine to mitigate the effects of explosion from landmines in a battlefield. The performed numerical simulations of blast loading of V-shaped plates consisted of various angles i.e. 60°, 90°, 120°, 150° and 180°; variable mass of explosives located at the central mid-point of the V-shaped vertex with various stand-off distances. It could be seen that the numerical simulations produced good agreement with the experimental results where the average difference was about 26.6%.

scholarly journals Modeling Replenishment of Ultrathin Liquid Perfluoropolyether Z Films on Solid Surfaces Using Monte Carlo Simulation

2014 ◽  
Vol 2014 ◽  
pp. 1-9
Author(s):  
M. S. Mayeed ◽  
T. Kato
Keyword(s):  
Monte Carlo Simulation ◽  
Monte Carlo ◽  
Liquid Films ◽  
Experimental Results ◽  
Solid Surfaces ◽  
Carbon Surface ◽  
Radius Of Gyration ◽  
Constant Multiple ◽  
Molecular Weights ◽  
Lattice Polymer

Applying the reptation algorithm to a simplified perfluoropolyether Z off-lattice polymer model an NVT Monte Carlo simulation has been performed. Bulk condition has been simulated first to compare the average radius of gyration with the bulk experimental results. Then the model is tested for its ability to describe dynamics. After this, it is applied to observe the replenishment of nanoscale ultrathin liquid films on solid flat carbon surfaces. The replenishment rate for trenches of different widths (8, 12, and 16 nms for several molecular weights) between two films of perfluoropolyether Z from the Monte Carlo simulation is compared to that obtained solving the diffusion equation using the experimental diffusion coefficients of Ma et al. (1999), with room condition in both cases. Replenishment per Monte Carlo cycle seems to be a constant multiple of replenishment per second at least up to 2 nm replenished film thickness of the trenches over the carbon surface. Considerable good agreement has been achieved here between the experimental results and the dynamics of molecules using reptation moves in the ultrathin liquid films on solid surfaces.

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