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Compact Toroid
Compact toroids are a class of toroidal plasma configurations that are self-stable, and whose configuration does not require magnet coils running through the center of the toroid. They are studied primarily in the field of fusion energy, where the lack of complex magnets and a simple geometry may allow the construction of dramatically simpler and less expensive fusion reactors. The two best studied compact toroids are the spheromak and field-reversed configuration (FRC). A third configuration, the particle ring, does not appear to have attractive performance. A CT containment system for plasma asymmetrically toroidally shaped by the containment, was first introduced into thought as a concept by Alfvén. The two examplar types; Field-reversed configuration plasma with a null toroid, firstly, is generally produced by prolate-theta-pinches with the necessarily existing field condition where the field magnetic bias is in a reversed situation. The second type has a non-null toroid, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Toroidal And Poloidal
Toroidal describes something which resembles or relates to a torus or toroid: Mathematics *Torus *Toroid, a surface of revolution which resembles a torus *Toroidal polyhedron *Toroidal coordinates, a three-dimensional orthogonal coordinate system *Toroidal and poloidal coordinates, directions relative to a torus of reference * Toroidal graph, a graph whose vertices can be placed on a torus such that no edges cross *Toroidal grid network, where an n-dimensional grid network is connected circularly in more than one dimension Engineering *Toroidal inductors and transformers, a type of electrical device * Toroidal and poloidal, directions in magnetohydrodynamics *Toroidal engine, an internal combustion engine with pistons that rotate within a toroidal space *Toroidal CVT, a type of continuously variable transmission *Toroidal reflector, a parabolic reflector which has a different focal distance depending on the angle of the mirror Other uses *Toroidal ring model The toroidal rin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Plasma (physics)
Plasma ()πλάσμα , Henry George Liddell, Robert Scott, ''A Greek English Lexicon'', on Perseus is one of the four fundamental states of matter. It contains a significant portion of charged particles – ions and/or s. The presence of these charged particles is what primarily sets plasma apart from the other fundamental states of matter. It is the most abundant form of ordi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Elsevier B
Elsevier () is a Dutch academic publishing company specializing in scientific, technical, and medical content. Its products include journals such as ''The Lancet'', ''Cell'', the ScienceDirect collection of electronic journals, '' Trends'', the '' Current Opinion'' series, the online citation database Scopus, the SciVal tool for measuring research performance, the ClinicalKey search engine for clinicians, and the ClinicalPath evidence-based cancer care service. Elsevier's products and services also include digital tools for data management, instruction, research analytics and assessment. Elsevier is part of the RELX Group (known until 2015 as Reed Elsevier), a publicly traded company. According to RELX reports, in 2021 Elsevier published more than 600,000 articles annually in over 2,700 journals; as of 2018 its archives contained over 17 million documents and 40,000 e-books, with over one billion annual downloads. Researchers have criticized Elsevier for its high profit margin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fusion Energy
Fusion power is a proposed form of power generation that would generate electricity by using heat from nuclear fusion reactions. In a fusion process, two lighter atomic nuclei combine to form a heavier nucleus, while releasing energy. Devices designed to harness this energy are known as fusion reactors. Research into fusion reactors began in the 1940s, but as of 2022, only one design, an inertial confinement laser-driven fusion machine at the US National Ignition Facility, has conclusively produced a positive fusion energy gain factor, i.e. more power output than input. Fusion processes require fuel and a confined environment with sufficient temperature, pressure, and confinement time to create a plasma in which fusion can occur. The combination of these figures that results in a power-producing system is known as the Lawson criterion. In stars, the most common fuel is hydrogen, and gravity provides extremely long confinement times that reach the conditions needed for fusion e ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Spheromak
A spheromak is an arrangement of plasma formed into a toroidal shape similar to a smoke ring. The spheromak contains large internal electric currents and their associated magnetic fields arranged so the magnetohydrodynamic forces within the spheromak are nearly balanced, resulting in long-lived (microsecond) confinement times without external fields. Spheromaks belong to a type of plasma configuration referred to as the compact toroids. A spheromak can be made and sustained using magnetic flux injection, leading to a dynomak. The physics of the spheromak and of collisions between spheromaks is similar to a variety of astrophysical events, like coronal loops and filaments, relativistic jets and plasmoids. They are particularly useful for studying magnetic reconnection events, when two or more spheromaks collide. Spheromaks are easy to generate using a "gun" that ejects spheromaks off the end of an electrode into a holding area, called the flux conserver. This has made them ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Field-reversed Configuration
A field-reversed configuration (FRC) is a type of plasma device studied as a means of producing nuclear fusion. It confines a plasma on closed magnetic field lines without a central penetration. In an FRC, the plasma has the form of a self-stable torus, similar to a smoke ring. FRCs are closely related to another self-stable magnetic confinement fusion device, the spheromak. Both are considered part of the compact toroid class of fusion devices. FRCs normally have a plasma that is more elongated than spheromaks, having the overall shape of a hollowed out sausage rather than the roughly spherical spheromak. FRCs were a major area of research in the 1960s and into the 1970s, but had problems scaling up into practical fusion triple products. Interest returned in the 1990s and , FRCs were an active research area. History The FRC was first observed in laboratories in the late 1950s during theta pinch experiments with a reversed background magnetic field. The first studies wer ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tokamak
A tokamak (; russian: токамáк; otk, 𐱃𐰸𐰢𐰴, Toḳamaḳ) is a device which uses a powerful magnetic field to confine plasma in the shape of a torus. The tokamak is one of several types of magnetic confinement devices being developed to produce controlled thermonuclear fusion power. , it was the leading candidate for a practical fusion reactor. Tokamaks were initially conceptualized in the 1950s by Soviet physicists Igor Tamm and Andrei Sakharov, inspired by a letter by Oleg Lavrentiev. The first working tokamak was attributed to the work of Natan Yavlinsky on the T-1 in 1958. It had been demonstrated that a stable plasma equilibrium requires magnetic field lines that wind around the torus in a helix. Devices like the z-pinch and stellarator had attempted this, but demonstrated serious instabilities. It was the development of the concept now known as the safety factor (labelled ''q'' in mathematical notation) that guided tokamak development; by arrang ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Beta (plasma Physics)
The beta of a plasma, symbolized by ''β'', is the ratio of the plasma pressure (''p'' = ''n'' ''k''B ''T'') to the magnetic pressure (''p''mag = ''B''²/2 ''μ''0). The term is commonly used in studies of the Sun and Earth's magnetic field, and in the field of fusion power designs. In the fusion power field, plasma is often confined using strong magnets. Since the temperature of the fuel scales with pressure, reactors attempt to reach the highest pressures possible. The costs of large magnets roughly scales like ''β½''. Therefore, beta can be thought of as a ratio of money out to money in for a reactor, and beta can be thought of (very approximately) as an economic indicator of reactor efficiency. For tokamaks, betas of larger than 0.05 or 5% are desired for economically viable electrical production. The same term is also used when discussing the interactions of the solar wind with various magnetic fields. For example, beta in the corona of the Sun is about 0.01. Backgroun ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Spherical Tokamak
A spherical tokamak is a type of fusion power device based on the tokamak principle. It is notable for its very narrow profile, or '' aspect ratio''. A traditional tokamak has a toroidal confinement area that gives it an overall shape similar to a donut, complete with a large hole in the middle. The spherical tokamak reduces the size of the hole as much as possible, resulting in a plasma shape that is almost spherical, often compared with a cored apple. The spherical tokamak is sometimes referred to as a spherical torus and often shortened to ST. The spherical tokamak is an offshoot of the conventional tokamak design. Proponents claim that it has a number of substantial practical advantages over these devices. For this reason the ST has generated considerable interest since the late 1980s. However, development remains effectively one generation behind traditional tokamak efforts like JET. Major experiments in the ST field include the pioneering START and MAST at Culham in the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
High Beta Fusion Reactor
The Lockheed Martin Compact Fusion Reactor (CFR) is a fusion power project at Lockheed Martin’s Skunk Works. Its high-beta configuration, which implies that the ratio of plasma pressure to magnetic pressure is greater than or equal to 1 (compared to tokamak designs' 0.05), allows a compact fusion reactor (CFR) design and expedited development. The CFR chief designer and technical team lead, Thomas McGuire studied fusion as a source of space propulsion in response to a NASA desire to improve travel times to Mars. History The project began in 2010, and was publicly presented at the Google Solve for X forum on February 7, 2013. In October 2014, Lockheed Martin announced a plan to "build and test a compact fusion reactor in less than a year with a prototype to follow within five years". In May 2016, Rob Weiss announced that Lockheed Martin continued to support the project and would increase its investment in it. Design CFR plans to achieve high beta (the ratio of plasma pressure ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
