Nuclear Fusion
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Author(s):  
Muchamad Rizky Nugraha ◽  
Andi Adriansyah

<span>Solar energy is a result of the nuclear fusion process in the form of a series of thermonuclear events that occur in the Sun's core. Solar radiation has a significant impact on the lives of all living things on earth. The uses, as mentioned earlier, are when the solar radiation received requires a certain amount and vice versa. As a result, a more accurate instrument of solar radiation is required. A specific instrument is typically used to measure solar radiation parameters. There are four solar radiation parameters: diffusion radiation, global radiation, direct radiation, and solar radiation duration. Thus, it needs to use many devices to measure radiation data. The paper designs to measure all four-radiation data by pyranometer with particular modification and shading device. This design results have a high correlation with a global standard with a value of R=0.73, diffusion with a value of R=0.60 and a sufficiently strong direct correlation with a value of R=0.56. It can be said that the system is much simpler, making it easier to monitor and log the various solar radiation parameters.</span>


2022 ◽  
Author(s):  
Xu Meng ◽  
Z H Wang ◽  
Dengke Zhang

Abstract In the future application of nuclear fusion, the liquid metal flows are considered to be an attractive option of the first wall of the Tokamak which can effectively remove impurities and improve the confinement of plasma. Moreover, the flowing liquid metal can solve the problem of the corrosion of the solid first wall due to high thermal load and particle discharge. In the magnetic confinement fusion reactor, the liquid metal flow experiences strong magnetic and electric, fields from plasma. In the present paper, an experiment has been conducted to explore the influence of electric and magnetic fields on liquid metal flow. The direction of electric current is perpendicular to that of the magnetic field direction, and thus the Lorentz force is upward or downward. A laser profilometer (LP) based on the laser triangulation technique is used to measure the thickness of the liquid film of Galinstan. The phenomenon of the liquid column from the free surface is observed by the high-speed camera under various flow rates, intensities of magnetic field and electric field. Under a constant external magnetic field, the liquid column appears at the position of the incident current once the external current exceeds a critical value, which is inversely proportional to the magnetic field. The thickness of the flowing liquid film increases with the intensities of magnetic field, electric field, and Reynolds number. The thickness of the liquid film at the incident current position reaches a maximum value when the force is upward. The distribution of liquid metal in the channel presents a parabolic shape with high central and low marginal. Additionally, the splashing, i.e., the detachment of liquid metal is not observed in the present experiment, which suggests a higher critical current for splashing to occur.


2022 ◽  
Vol 14 (2) ◽  
pp. 899
Author(s):  
Zaida Troya ◽  
Rafael Esteban ◽  
Enrique Herrera-Viedma ◽  
Antonio Peña-García

Nuclear facilities are a main milestone in the long way to sustainable energy. Beyond the well-known fission centrals, the necessity of cleaner, more efficient and almost unlimited energy reducing waste to almost zero is a major challenge in the next decades. This is the case with nuclear fusion. Different experimental installations to definitively control this nuclear power are proliferating in different countries. However, citizens in the surroundings of cities and villages where these installations are going to be settled are frequently reluctant because of doubts about the expected benefits and the potential hazards. In this framework, knowing the opinion of people and their perception of experimental fusion facilities is essential for researchers, administrations and rulemaking bodies planning future fusion plants. This is the case for IFMIF-DONES, a neutron irradiation facility to determine the most suitable materials for the future fusion reactors. The construction of this installation is starting in Escúzar (Granada, Spain), and this work presents a large survey among 311 people living or working in the village. Their perception, fears, hopes and other variables are analyzed, and the conclusions for future installations and their impact on the energy policy are presented.


2022 ◽  
Vol 5 (6) ◽  
pp. 102-115
Author(s):  
Toshihiko Yoshimura ◽  
Masataka Ijiri ◽  
Kazunori Sato

In the present work, a strong magnetic field was applied near the outlet of the water jet nozzle to promote the generation of multifunction cavitation bubbles. Because these bubbles contained charged species, the bubbles experienced a Lorentz force due to the magnetic field and collided with greater force. As such, the internal bubble pressure exceeded the threshold value required for fusion to occur. The expansion of these charged bubbles in response to ultrasonic irradiation affected adjacent charged bubbles so that the energy density of the atoms in the bubbles was greater than the fusion threshold. The results of this work strongly suggest that the formation of bubbles via the UTPC process in conjunction with a strong magnetic field may result in bubble fusion.


2021 ◽  
Vol 62 (1) ◽  
pp. 010204
Author(s):  
Christian Theiler

Author(s):  
Diogo R. Ferreira ◽  
Tiago A. Martins ◽  
Paulo Rodrigues

Abstract In the nuclear fusion community, there are many specialized techniques to analyze the data coming from a variety of diagnostics. One of such techniques is the use of spectrograms to analyze the magnetohydrodynamic (MHD) behavior of fusion plasmas. Physicists look at the spectrogram to identify the oscillation modes of the plasma, and to study instabilities that may lead to plasma disruptions. One of the major causes of disruptions occurs when an oscillation mode interacts with the wall, stops rotating, and becomes a locked mode. In this work, we use deep learning to predict the occurrence of locked modes from MHD spectrograms. In particular, we use a Convolutional Neural Network (CNN) with Class Activation Mapping (CAM) to pinpoint the exact behavior that the model thinks is responsible for the locked mode. Surprisingly, we find that, in general, the model explanation agrees quite well with the physical interpretation of the behavior observed in the spectrogram.


2021 ◽  
Vol 62 (1) ◽  
pp. 010203
Author(s):  
Nathan T Howard

2021 ◽  
Vol 11 (24) ◽  
pp. 11653
Author(s):  
Michael Rieth ◽  
Michael Dürrschnabel ◽  
Simon Bonk ◽  
Ute Jäntsch ◽  
Thomas Bergfeldt ◽  
...  

Plasma facing components for energy conversion in future nuclear fusion reactors require a broad variety of different fabrication processes. We present, along a series of studies, the general effects and the mutual impact of these processes on the properties of the EUROFER97 steel. We also consider robust fabrication routes, which fit the demands for industrial environments. This includes heat treatment, fusion welding, machining, and solid-state bonding. Introducing and following a new design strategy, we apply the results to the fabrication of a first-wall mock-up, using the same production steps and processes as for real components. Finally, we perform high heat flux tests in the Helium Loop Karlsruhe, applying a few hundred short pulses, in which the maximum operating temperature of 550 °C for EUROFER97 is finally exceeded by 100 K. Microstructure analyses do not reveal critical defects or recognizable damage. A distinct ferrite zone at the EUROFER/ODS steel interface is detected. The main conclusions are that future breeding blankets can be successfully fabricated by available industrial processes. The use of ODS steel could make a decisive difference in the performance of breeding blankets, and the first wall should be completely fabricated from ODS steel or plated by an ODS carbon steel.


2021 ◽  
Author(s):  
Ji Hwan Lim ◽  
Minkyu Park

Abstract For the cooling system of the future, nuclear fusion tokamak, to operate stably and continuously, it is important to identify potential hazards that may occur in the system in advance. Among the various potential hazards associated with the nuclear fusion tokamak, the onset of nucleate boiling (ONB) is a point at which the heat-transfer mechanism changes dramatically and is a crucial factor that must be addressed. In particular, the equipment inside the tokamak is loaded with a heat flux of several MW/m2 under single-side heating conditions, and it is important to predict the ONB under these special heating conditions. Therefore, in this study, the ONB of a flat heat sink was experimentally investigated under highly subcooled flow conditions. Based on the physical understanding of the thermo-hydraulic aspect of the ONB, the wall temperature gradient change point, which is mainly used in the subcooled flow condition, was selected as the ONB detection criterion. Trends in the ONB heat flux change were analyzed as representative system parameters that can be tuned in the cooling system, such as subcooling, mass flow rate, and pressure. In addition, the ONB correlations developed in the previous studies were evaluated for predicting the performance under one-side high heat load conditions. However, the large difference in the experimental conditions (range of system parameters and heating conditions) and the fact that the influence of system parameters was not reflected in the correlation resulted in high error rates. Therefore, the ONB correlation that can be used in the tokamak heat flux condition was newly developed through a dimensional analysis that can effectively reflect the influences in the correlation through dimensionless numbers. The developed correlation can be of great help in designing a diverter or blanket cooling system and establishing an operational strategy.


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