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Taylor State
In plasma physics, a Taylor state is the minimum energy state of a plasma while the plasma is conserving magnetic flux. This was first proposed by John Bryan Taylor in 1974 and he backed up this claim using data from the ZETA machine. Taylor-States are critical to operating both the Dynomak and the Reversed field pinch - both run in a Taylor State. Examples In 1974, Dr. John B Taylor proposed that a spheromak could be formed by inducing a magnetic flux into a loop plasma. The plasma would then relax naturally into a spheromak also known as a Taylor State. This process worked if the plasma: * Conserved the total magnetic flux * Minimized the total energy These claims were later checked by Marshall Rosenbluth in 1979. In 1974, Dr. Taylor could only use results from the ZETA pinch device to back up these claims. But, since then, Taylor states have been formed in multiple machines including: * Compact Torus Experiment (CTX) at Los Alamos. The CTX operated from ~1979 to ... [...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 . It contains a significant portion of charged particles – s 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 |
Principle Of Minimum Energy
The principle of minimum energy is essentially a restatement of the second law of thermodynamics. It states that for a closed system, with constant external parameters and entropy, the internal energy will decrease and approach a minimum value at equilibrium. External parameters generally means the volume, but may include other parameters which are specified externally, such as a constant magnetic field. In contrast, for isolated systems (and fixed external parameters), the second law states that the entropy will increase to a maximum value at equilibrium. An isolated system has a fixed total energy and mass. A closed system, on the other hand, is a system which is connected to another, and cannot exchange matter (i.e. particles), but other forms of energy (e.g. heat), with the other system. If, rather than an isolated system, we have a closed system, in which the entropy rather than the energy remains constant, then it follows from the first and second laws of thermodynamics th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Plasma (physics)
Plasma () 1, where \nu_ is the electron gyrofrequency and \nu_ is the electron collision rate. It is often the case that the electrons are magnetized while the ions are not. Magnetized plasmas are ''anisotropic'', meaning that their properties in the direction parallel to the magnetic field are different from those perpendicular to it. While electric fields in plasmas are usually small due to the plasma high conductivity, the electric field associated with a plasma moving with velocity \mathbf in the magnetic field \mathbf is given by the usual Lorentz force, Lorentz formula \mathbf = -\mathbf\times\mathbf, and is not affected by Debye shielding. Mathematical descriptions To completely describe the state of a plasma, all of the particle locations and velocities that describe the electromagnetic field in the plasma region would need to be written down. However, it is generally not practical or necessary to keep track of all the particles in a plasma. Therefore, plasma physicist ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Magnetic Flux
In physics, specifically electromagnetism, the magnetic flux through a surface is the surface integral of the normal component of the magnetic field B over that surface. It is usually denoted or . The SI unit of magnetic flux is the weber (Wb; in derived units, volt–seconds), and the CGS unit is the maxwell. Magnetic flux is usually measured with a fluxmeter, which contains measuring coils and electronics, that evaluates the change of voltage in the measuring coils to calculate the measurement of magnetic flux. Description The magnetic interaction is described in terms of a vector field, where each point in space is associated with a vector that determines what force a moving charge would experience at that point (see Lorentz force). Since a vector field is quite difficult to visualize at first, in elementary physics one may instead visualize this field with field lines. The magnetic flux through some surface, in this simplified picture, is proportional to the num ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
John Bryan Taylor
John Bryan Taylor (born 26 December 1928) is a British physicist known for his contributions to plasma physics and their application in the field of fusion energy. Notable among these is the development of the "Taylor state", describing a minimum-energy configuration that conserves magnetic helicity. Another development was his work on the ballooning transformation, which describes the motion of plasma in toroidal (donut) configurations, which are used in the fusion field. Taylor has also made contributions to the theory of the Earth's Dynamo, including the Taylor constraint. Early life and career Taylor was born in Birmingham. He served in the Royal Air Force from 1950–1952, and then took his PhD at Birmingham University in 1955. Upon graduation, he joined the Atomic Weapons Establishment at Aldermaston, and in 1962 moved to the Culham Laboratory, where he became Chief Physicist. He held several other positions during this period, including the Commonwealth Fund Fellow at ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
ZETA
Zeta (, ; uppercase Ζ, lowercase ζ; grc, ζῆτα, el, ζήτα, label= Demotic Greek, classical or ''zē̂ta''; ''zíta'') is the sixth letter of the Greek alphabet. In the system of Greek numerals, it has a value of 7. It was derived from the Phoenician letter zayin . Letters that arose from zeta include the Roman Z and Cyrillic З. Name Unlike the other Greek letters, this letter did not take its name from the Phoenician letter from which it was derived; it was given a new name on the pattern of beta, eta and theta. The word ''zeta'' is the ancestor of ''zed'', the name of the Latin letter Z in Commonwealth English. Swedish and many Romanic languages (such as Italian and Spanish) do not distinguish between the Greek and Roman forms of the letter; "''zeta''" is used to refer to the Roman letter Z as well as the Greek letter. Uses Letter The letter ζ represents the voiced alveolar fricative in Modern Greek Modern Greek (, , or , ''Kiní Neoellinikí Gl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Spheromak Formation In Dynomak - Model
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 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dynomak
Dynomak is a spheromak fusion reactor concept developed by the University of Washington using U.S. Department of Energy funding.Michelle Ma"UW fusion reactor concept could be cheaper than coal" ''University of Washington'', October 8, 2014Evan Ackerman"Inside the Dynomak" ''IEEE Spectrum'', November 26, 2014 A dynomak is defined as a spheromak that is started and maintained by magnetic flux injection. The dynomak is formed when an alternating current is used to induce a magnetic flux into plasma. A transformer uses the same induction process to create a secondary current. Once formed, the plasma inside the Dynomak relaxes into its lowest energy state, while conserving overall flux.Taylor, J. Brian. "Relaxation of toroidal plasma and generation of reverse magnetic fields." Physical Review Letters 33.19 (1974): 1139. This is known as a Taylor state and inside the machine what is formed is a plasma structure called a spheromak. The Dynomak is a kind of Spheromak that is starte ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Reversed Field Pinch
A reversed-field pinch (RFP) is a device used to produce and contain near-thermonuclear Plasma (physics), plasmas. It is a Pinch (magnetic fusion), toroidal pinch which uses a unique magnetic field configuration as a scheme to magnetically confine a plasma, primarily to study magnetic confinement fusion. Its magnetic geometry is somewhat different from that of the more common tokamak. As one moves out radially, the portion of the magnetic field pointing toroidally reverses its direction, giving rise to the term ''reversed field''. This configuration can be sustained with comparatively lower fields than that of a tokamak of similar power density. One of the disadvantages of this configuration is that it tends to be more susceptible to non-linear effects and turbulence. This makes it a useful system for studying non-ideal (resistive) magnetohydrodynamics. RFPs are also used in studying astrophysical plasmas, which share many common features. The largest Reversed Field Pinch ... [...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] |
