Post-Test Numerical Analysis of a Helium-Cooled Breeding Blanket First Wall under LOFA Conditions with the MELCOR Fusion Code

The validation of numerical tools employed in the analysis of incidental transients in a fusion reactor is a topic of main concern. KIT is taking part in this task providing both experimental data and by performing numerical analysis in support of the main codes used for the safety analyses of the Helium Cooled Pebble Bed (HCPB) blanket concept. In recent years, an experimental campaign has been performed in the KIT-HELOKA facility to investigate the behavior of a First Wall Mock-Up (FWMU) under Loss Of Flow Accident (LOFA) conditions. The aim of the experimental campaign was twofold: to check the expected DEMO thermal-hydraulics conditions during normal and off-normal conditions and to provide robust data for code validation. The present work is part of these validation efforts, and it deals with the analysis of the LOFA experimental campaign with the system code MELCOR 1.8.6 for fusion. A best-estimate methodology has been used in support of this analysis to ease the distinction between user’s assumptions and code limitations. The numerical analyses are here described together with their goals, achievements, and lesson learnt.

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Experiments and numerical analysis of eddy currents in the first wall of a fusion reactor

IEEE Transactions on Magnetics ◽

10.1109/20.106455 ◽

1990 ◽

Vol 26 (2) ◽

pp. 869-872 ◽

Cited By ~ 7

Author(s):

M. Hashimoto ◽

H. Hashizume ◽

T. Sugiura ◽

T. Takagi ◽

K. Miya ◽

...

Keyword(s):

Numerical Analysis ◽

Eddy Currents ◽

Fusion Reactor ◽

First Wall

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Theoretical Calculation and Numerical Investigation for the Effective Thermal Conductivity of Packed Li2TiO3 Pebble Bed

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.953-954.627 ◽

2014 ◽

Vol 953-954 ◽

pp. 627-630

Author(s):

Hao Ran Cao ◽

Rong Hua Huang ◽

Jun Heng Li

Keyword(s):

Experimental Data ◽

Thermal Conductivity ◽

Numerical Simulation ◽

Theoretical Calculation ◽

Effective Thermal Conductivity ◽

Fusion Reactor ◽

Lithium Titanate ◽

Tritium Breeding ◽

Pebble Bed ◽

Fusion Reactor Blanket

Lithium titanate (Li2TiO3) in form of packed pebble bed is promising concept for breeder material in the fusion reactor blanket, and worldwide efforts have been dedicated to its R&D in the last two decade. Li2TiO3 pebble beds with the efforts of tritium breeding and thermal removing play a major role in the thermal performance of the fusion reactor blanket. Specifically, the effective thermal conductivity of Li2TiO3 is an important parameter for the design and thermal mechanical of fusion reactor blanket. The theoretical calculation and numerical simulation for the effective thermal conductivity of Li2TiO3 pebble bed are performed in this paper. The theoretical equations and modeling result for the thermal conductivity of Li2TiO3 pebble bed are given and compared with the experimental data. The results show that the effective thermal conductivity of Li2TiO3 pebble bed can be preliminarily obtained by numerical simulation and theoretical calculation.

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Alignment of small He-Bubbles during in situ deformation of Al-foils

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100109124 ◽

1978 ◽

Vol 36 (1) ◽

pp. 396-397

Author(s):

E. Ruedl ◽

P. Schiller

Keyword(s):

Fusion Reactor ◽

Matrix Material ◽

Fusion Reactors ◽

First Wall ◽

Potential Matrix ◽

In Situ Deformation ◽

Α Particles ◽

Metal Aluminium

The low Z metal aluminium is a potential matrix material for the first wall in fusion reactors. A drawback in the application of A1 is the rel= atively high amount of He produced in it under fusion reactor conditions. Knowledge about the behaviour of He during irradiation and deformation in Al, especially near the surface, is therefore important.Using the TEM we have studied Al disks of 3 mm diameter and 0.2 mm thickness, which were perforated at the centre by double jet polishing. These disks were bombarded at∽200°C to various doses with α-particles, impinging at any angle and energy up to 1.5 MeV at both surfaces. The details of the irradiations are described in Ref.1. Subsequent observation indicated that in such specimens uniformly distributed He-bubbles are formed near the surface in a layer several μm thick (Fig.1).After bombardment the disks were deformed at 20°C during observation by means of a tensile device in a Philips EM 300 microscope.

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A Study of Yielding and Plasticity of Rapid Prototyped ABS

Mathematics ◽

10.3390/math9131495 ◽

2021 ◽

Vol 9 (13) ◽

pp. 1495

Author(s):

Dan-Andrei Șerban ◽

Cosmin Marșavina ◽

Alexandru Viorel Coșa ◽

George Belgiu ◽

Radu Negru

Keyword(s):

Experimental Data ◽

Stress State ◽

Plastic Flow ◽

Plane Stress ◽

Yield Criterion ◽

Numerical Analyses ◽

Flow Potential ◽

Stress States ◽

State Configuration

In this article, the yielding and plastic flow of a rapid-prototyped ABS compound was investigated for various plane stress states. The experimental procedures consisted of multiaxial tests performed on an Arcan device on specimens manufactured through photopolymerization. Numerical analyses were employed in order to determine the yield points for each stress state configuration. The results were used for the calibration of the Hosford yield criterion and flow potential. Numerical analyses performed on identical specimen models and test configurations yielded results that are in accordance with the experimental data.

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An Estimator for the Kinematic Behaviour of a Mobile Robot Subject to Large Lateral Slip

Applied Sciences ◽

10.3390/app11041594 ◽

2021 ◽

Vol 11 (4) ◽

pp. 1594 ◽

Cited By ~ 1

Author(s):

Andrea Botta ◽

Paride Cavallone ◽

Luigi Tagliavini ◽

Luca Carbonari ◽

Carmen Visconte ◽

...

Keyword(s):

Experimental Data ◽

Mobile Robot ◽

Trajectory Planning ◽

Kinematic Model ◽

Close Connection ◽

Wheel Slip ◽

Robot Architecture ◽

Experimental Campaign ◽

Base Concept ◽

Kinematic Behaviour

In this paper, the effects of wheel slip compensation in trajectory planning for mobile tractor-trailer robot applications are investigated. Firstly, a kinematic model of the proposed robot architecture is marked out, then an experimental campaign is done to identify if it is possible to kinematically compensate trajectories that otherwise would be subject to large lateral slip. Due to the close connection to the experimental data, the results shown are valid only for Epi.q, the prototype that is the main object of this manuscript. Nonetheless, the base concept can be usefully applied to any mobile robot subject to large lateral slip.

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Numerical analysis of supersonic jet flow and dust transport induced by air ingress in a fusion reactor

Nuclear Science and Techniques ◽

10.1007/s41365-021-00912-z ◽

2021 ◽

Vol 32 (7) ◽

Author(s):

Bu-Er Wang ◽

Shi-Chao Zhang ◽

Zhen Wang ◽

Jiang-Tao Jia ◽

Zhi-Bin Chen

Keyword(s):

Numerical Analysis ◽

Fusion Reactor ◽

Supersonic Jet ◽

Jet Flow ◽

Dust Transport ◽

Air Ingress

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Special Features of First-Wall Heat Transfer in Liquid-Metal Fusion Reactor Blankets

Fusion Technology ◽

10.13182/fst87-a25054 ◽

1987 ◽

Vol 12 (1) ◽

pp. 104-113 ◽

Cited By ~ 4

Author(s):

K. Taghavi ◽

M. S. Tillack ◽

H. Madarame

Keyword(s):

Heat Transfer ◽

Liquid Metal ◽

Fusion Reactor ◽

Wall Heat Transfer ◽

First Wall

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Characteristics of irradiation creep in the first wall of a fusion reactor

Journal of Nuclear Materials ◽

10.1016/0022-3115(82)90772-3 ◽

1981 ◽

Vol 104 ◽

pp. 1245-1250 ◽

Cited By ~ 2

Author(s):

W.A. Coghlan ◽

L.K. Mansur

Keyword(s):

Fusion Reactor ◽

First Wall ◽

Irradiation Creep

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Updated Design and Development Route for CH HCCB TBM and its Mockup

Volume 5: Fuel Cycle, Radioactive Waste Management and Decommissioning; Reactor Physics and Transport Theory; Nuclear Education, Public Acceptance and Related Issues; Instrumentation and Controls; Fusion Engineering ◽

10.1115/icone21-16046 ◽

2013 ◽

Author(s):

Gang Hu ◽

Kaiming Feng ◽

Zhou Zhao ◽

Guoshu Zhang ◽

Qijie Wang ◽

...

Keyword(s):

Fusion Reactor ◽

Surface Heat ◽

Maximum Temperature ◽

First Wall ◽

Total Stress ◽

Design And Development ◽

Tritium Production ◽

Radial Length ◽

Development Route ◽

Purge Gas

Chinese helium-cooled ceramics breeder test blanket module (CH HCCB TBM) is determined to be tested in ITER machine to get data for fusion reactor design and development in future. Chinese TBM is designed to occupy half of port C with 484mm in torroidal and 1660mm in poloidal. Radial length is 675mm. TBM is composed of box, 12 submodules and independent backplate. Box formed by first wall, grids and caps have 12 caivities to hold submodules. Box and submodules are supported by backplate by welding. Backplate distribute helium with flow rate 1.36kg/s to cool first wall and then part of it go out of TBM by bypass. The rest 0.77kg/s go on to cool caps and girds first and then cool submodules. Submodules with dimensions 250mm×202mm×318mm have independent cooling and purging systems connected to backplate manifold systems. In a submodule, two U-shaped structures hold breeding material Li4SiO4 pebbles. Out of the structure filled beryllium pebbles. Neutronics results show that tritium production is ∼64mg/FPD. Maximum temperature 538°C of structure material occurs in the front of first wall with surface heat flux 0.5MW/m2. Maximum total stress at first wall is 471MPa at 394°C; that in submodules is 426MPa at 400°C; that in backplate is 526MPa at 410°C, In order to explore development technologies for the TBM, a mockup with dimensions 484mm (torroidal)×592mm (poloidal)×675mm (radial) has been designed. The mockup with similar structure ignores bypass and purge gas systems. In the mockup, there’s only one submodule and the other three are replaced by submodule replacements. By discussions and investigations, development route has been decided and the mockup is being fabricated.

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