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Science Action: How does a magnetic field confine a plasma?
Science Action: How does a magnetic field confine a plasma?
Published: 2014/06/10
Channel: Science Action
Magnetic Confinement of Nuclear Fusion
Magnetic Confinement of Nuclear Fusion
Published: 2014/04/24
Channel: AK LECTURES
Magnetic confinement fusion - Video Learning - WizScience.com
Magnetic confinement fusion - Video Learning - WizScience.com
Published: 2015/09/10
Channel: Wiz Science™
Magnetic Confinement Concepts
Magnetic Confinement Concepts
Published: 2013/11/17
Channel: Animations for Physics and Astronomy
Magnetic Confinement Fusion
Magnetic Confinement Fusion
Published: 2013/04/26
Channel: Michael Fendler
Plasma Magnetic Confinement In Glass
Plasma Magnetic Confinement In Glass
Published: 2015/01/31
Channel: Physics Is Wonderful
Building a homemade magnetic confinement fusion reactor
Building a homemade magnetic confinement fusion reactor
Published: 2012/01/13
Channel: Lloyd Share
Fusion Power Explained – Future or Failure
Fusion Power Explained – Future or Failure
Published: 2016/11/10
Channel: Kurzgesagt – In a Nutshell
ITER Fusion Reactor
ITER Fusion Reactor
Published: 2012/10/08
Channel: Jamison Daniel
"#MCF: The physics of magnetic confinement in 180 minutes I" - Michael Barnes
"#MCF: The physics of magnetic confinement in 180 minutes I" - Michael Barnes
Published: 2016/07/20
Channel: Institute for Advanced Study
Inertial Confinement Fusion
Inertial Confinement Fusion
Published: 2015/01/16
Channel: OaklandLYM
Fusion Power On The Horizon
Fusion Power On The Horizon
Published: 2015/11/16
Channel: 10 Reasons Why Show
Fusion An Introduction to the Physics and Technology of Magnetic Confinement Fusion
Fusion An Introduction to the Physics and Technology of Magnetic Confinement Fusion
Published: 2017/03/03
Channel: Krupa
Fusion, Volume 1 ,Part A Magnetic Confinement Vol 1
Fusion, Volume 1 ,Part A Magnetic Confinement Vol 1
Published: 2017/06/18
Channel: cris kekey
Fusion An Introduction to the Physics and Technology of Magnetic Confinement Fusion
Fusion An Introduction to the Physics and Technology of Magnetic Confinement Fusion
Published: 2017/06/18
Channel: cris kekey
The Fusion Driven Rocket: Animation
The Fusion Driven Rocket: Animation
Published: 2013/03/28
Channel: FusionDrivenRocket
Magnetic confinement fusion
Magnetic confinement fusion
Published: 2015/11/12
Channel: Hiren Shah
Nuclear Fusion 500 Terawatt Laser at the National Ignition Facility
Nuclear Fusion 500 Terawatt Laser at the National Ignition Facility
Published: 2012/07/16
Channel: Muon Ray
Lesson 14 - Magnetic Confinement And The Earth
Lesson 14 - Magnetic Confinement And The Earth's Aurora (Physics Tutor)
Published: 2016/08/19
Channel: mathtutordvd
Fusion Plasma Physics and ITER - An Introduction (1/4)
Fusion Plasma Physics and ITER - An Introduction (1/4)
Published: 2012/05/16
Channel: Teknociencia
6c Fusion: inertial and magnetic approaches
6c Fusion: inertial and magnetic approaches
Published: 2015/09/15
Channel: Plasma Physics and Applications
Fusion An Introduction to the Physics and Technology of Magnetic Confinement Fusion
Fusion An Introduction to the Physics and Technology of Magnetic Confinement Fusion
Published: 2017/03/07
Channel: Paul B
Magnetic Confinement Fusion Driven Thermonuclear Energy
Magnetic Confinement Fusion Driven Thermonuclear Energy
Published: 2017/06/16
Channel: ikka tigris
Magnetic Fusion Practice Session # 2 - Nurture Your Dreams
Magnetic Fusion Practice Session # 2 - Nurture Your Dreams
Published: 2012/10/16
Channel: Piratheepan Jeyakumar
Fusion   Magnetic Confinement   Home Energy Reactor
Fusion Magnetic Confinement Home Energy Reactor
Published: 2017/04/20
Channel: Nicholas T
Download Fusion An Introduction to the Physics and Technology of Magnetic Confinement Fusion
Download Fusion An Introduction to the Physics and Technology of Magnetic Confinement Fusion
Published: 2017/02/22
Channel: Jamie S
Lockheed Martin Compact Magnetic Fusion Project
Lockheed Martin Compact Magnetic Fusion Project
Published: 2014/11/20
Channel: TopGunMilitary
Fusion An Introduction to the Physics and Technology of Magnetic Confinement Fusion
Fusion An Introduction to the Physics and Technology of Magnetic Confinement Fusion
Published: 2017/02/07
Channel: Josefina
Polywell Fusion: Electrostatic Fusion in a Magnetic Cusp
Polywell Fusion: Electrostatic Fusion in a Magnetic Cusp
Published: 2016/08/04
Channel: Microsoft Research
#MCF: The Physics of Magnetic Confinement in 180 Minutes (Part 2) - Michael Barnes
#MCF: The Physics of Magnetic Confinement in 180 Minutes (Part 2) - Michael Barnes
Published: 2016/07/22
Channel: Institute for Advanced Study
Fusion Energy Production by Deuterium Particle Injection
Fusion Energy Production by Deuterium Particle Injection
Published: 2012/09/28
Channel: Jamison Daniel
Fusion An Introduction to the Physics and Technology of Magnetic Confinement Fusion Pdf Book
Fusion An Introduction to the Physics and Technology of Magnetic Confinement Fusion Pdf Book
Published: 2016/06/03
Channel: Linda. A
Magnetic Fusion Energy: Earl  Marmar
Magnetic Fusion Energy: Earl Marmar
Published: 2016/01/15
Channel: MIT Plasma Science and Fusion Center
6d Simple design of a magnetic fusion reactor
6d Simple design of a magnetic fusion reactor
Published: 2015/09/15
Channel: Plasma Physics and Applications
Superconductors - super-magnetic confinement!
Superconductors - super-magnetic confinement!
Published: 2013/09/27
Channel: EFDAJET
Magnetic Confinement Simulation with JavaScript & D3.js
Magnetic Confinement Simulation with JavaScript & D3.js
Published: 2015/10/13
Channel: Matthew Loftus
Nuclear Fusion: Clean Power for the Next Hundred Centuries
Nuclear Fusion: Clean Power for the Next Hundred Centuries
Published: 2009/09/10
Channel: GoogleTechTalks
CPEP PHYSICS Magnetic Confinement
CPEP PHYSICS Magnetic Confinement
Published: 2012/07/30
Channel: Cheryl Harper
Understanding turbulence to use magnetically confined fusion
Understanding turbulence to use magnetically confined fusion
Published: 2008/11/17
Channel: KyleBGustafson
discovering physics magnetic confinement
discovering physics magnetic confinement
Published: 2013/01/01
Channel: mrcotton333
Magnetic Fusion Experiments
Magnetic Fusion Experiments
Published: 2014/04/30
Channel: Anna Malcom
K-Star Tokamac Magnetic Fusion Plasma Reactor Power for the Future
K-Star Tokamac Magnetic Fusion Plasma Reactor Power for the Future
Published: 2010/05/25
Channel: freeenergy4everyone
Books of Nuclear Fusion Half a Century of Magnetic Confinement Fusion Research Plasma Physics
Books of Nuclear Fusion Half a Century of Magnetic Confinement Fusion Research Plasma Physics
Published: 2015/10/21
Channel: Evelyn McKinney
Download Fusion Volume 1 Magnetic Confinement Part B Book
Download Fusion Volume 1 Magnetic Confinement Part B Book
Published: 2016/09/19
Channel: F. Bingham
Modern Industry - HiPER - European fast ignition fusion project
Modern Industry - HiPER - European fast ignition fusion project
Published: 2015/11/27
Channel: Ionor Rea's Evolution channel
Fusion and magnetic confinement of high temperature plasmas | Фридрих Вагнер | Лекториум
Fusion and magnetic confinement of high temperature plasmas | Фридрих Вагнер | Лекториум
Published: 2014/01/21
Channel: Лекториум
Download Fusion An Introduction to the Physics and Technology of Magnetic Confinement Fusion Pdf
Download Fusion An Introduction to the Physics and Technology of Magnetic Confinement Fusion Pdf
Published: 2017/02/28
Channel: V. Donzello
High-flux helium and hydrogen plasma exposure of materials for magnetic fusion
High-flux helium and hydrogen plasma exposure of materials for magnetic fusion
Published: 2017/02/07
Channel: BerkeleyNUC
Nuclear Fusion , the future of energy ..tokamak technology to clean energy
Nuclear Fusion , the future of energy ..tokamak technology to clean energy
Published: 2015/10/19
Channel: Alex Franks
Alcator C-Mod - Video Learning - WizScience.com
Alcator C-Mod - Video Learning - WizScience.com
Published: 2015/09/24
Channel: Wiz Science™
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WIKIPEDIA ARTICLE

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The reaction chamber of the TCV, an experimental tokamak fusion reactor at École polytechnique fédérale de Lausanne, Lausanne, Switzerland which has been used in research since it was built in 1992. The characteristic torus-shaped chamber is clad with graphite to help withstand the extreme heat (the shape is distorted by the camera's fisheye lens).

Magnetic confinement fusion is an approach to generating thermonuclear fusion power that uses magnetic fields to confine the hot fusion fuel in the form of a plasma. Magnetic confinement is one of two major branches of fusion energy research, the other being inertial confinement fusion. The magnetic approach is more highly developed and is usually considered more promising for practical power production, as it has reached the point of energy breakeven. Construction of a 500-MW power generating fusion plant using tokamak magnetic confinement geometry, the ITER, began in France in 2007 and is scheduled to begin operation 2035.

Fusion reactions combine light atomic nuclei such as hydrogen to form heavier ones such as helium, producing energy. In order to overcome the electrostatic repulsion between them, the nuclei must have a temperature of several tens of millions of degrees, under which conditions they no longer form neutral atoms but exist in the plasma state. In addition, sufficient density and energy confinement are required, as specified by the Lawson criterion.

Magnetic confinement fusion attempts to create the conditions needed for fusion energy production by using the electrical conductivity of the plasma to contain it with magnetic fields, since no solid container could withstand the extreme heat of the plasma. The basic concept can be thought of in a fluid picture as a balance between magnetic pressure and plasma pressure, or in terms of individual particles spiraling along magnetic field lines.

The pressure achievable is usually on the order of one bar with a confinement time up to a few seconds.[1] In contrast, inertial confinement has a much higher pressure but a much lower confinement time. Most magnetic confinement schemes also have the advantage of being more or less steady state, as opposed to the inherently pulsed operation of inertial confinement.

The simplest magnetic configuration is a solenoid, a long cylinder wound with magnetic coils producing a field with the lines of force running parallel to the axis of the cylinder. Such a field would hinder the ions and electrons from being lost radially, but not from being lost from the ends of the solenoid.

There are two approaches to solving this problem. One is to try to stop up the ends of the solenoid with magnetic mirrors. The other is to eliminate the ends altogether by bending the field lines around to close on themselves by making the solenoid and confinement chamber in the shape of a torus (doughnut). This type of machine, called a tokamak, is used in the latest prototype plants.

Magnetic mirrors[edit]

A major area of research in the early years of fusion energy research was the magnetic mirror. Most early mirror devices attempted to confine plasma near the focus of a non-planar magnetic field, or to be more precise, two such mirrors located close to each other and oriented at right angles. In order to escape the confinement area, nuclei had to enter a small annular area near each magnet. It was known that nuclei would escape through this area, but by adding and heating fuel continually it was felt this could be overcome. As development of mirror systems progressed, additional sets of magnets were added to either side, meaning that the nuclei had to escape through two such areas before leaving the reaction area entirely. A highly developed form, the Mirror Fusion Test Facility (MFTF), used two mirrors at either end of a solenoid to increase the internal volume of the reaction area.

Toroidal machines[edit]

Stellarators[edit]

An early attempt to build a magnetic confinement system was the stellarator, introduced by Lyman Spitzer in 1951. Essentially the stellarator consists of a torus that has been cut in half and then attached back together with straight "crossover" sections to form a figure-8. This has the effect of propagating the nuclei from the inside to outside as it orbits the device, thereby canceling out the drift across the axis, at least if the nuclei orbit fast enough. Newer versions of the stellarator design have replaced the "mechanical" drift cancellation with additional magnets that "wind" the field lines into a helix to cause the same effect.

Tokamaks[edit]

Tokamak magnetic fields.

In 1968 Russian research on the toroidal tokamak was first presented in public, with results that far outstripped existing efforts from any competing design, magnetic or not. Since then the majority of effort in magnetic confinement has been based on the tokamak principle. In the tokamak a current is periodically driven through the plasma itself, creating a field "around" the torus that combines with the toroidal field to produce a winding field in some ways similar to that in a modern stellarator, at least in that nuclei move from the inside to the outside of the device as they flow around it.

In 1991, START was built at Culham, UK, as the first purpose built spherical tokamak. This was essentially a spheromak with an inserted central rod. START produced impressive results, with β values at approximately 40% - three times that produced by standard tokamaks at the time. The concept has been scaled up to higher plasma currents and larger sizes, with the experiments NSTX (US), MAST (UK) and Globus-M (Russia) currently running. Spherical tokamaks have improved stability properties compared to conventional tokamaks and as such the area is receiving considerable experimental attention. However spherical tokamaks to date have been at low toroidal field and as such are impractical for fusion neutron devices.

Other[edit]

Some more novel configurations produced in toroidal machines are the reversed field pinch and the Levitated Dipole Experiment.

Compact toroids[edit]

Compact toroids, e.g. the spheromak and the Field-Reversed Configuration, attempt to combine the good confinement of closed magnetic surfaces configurations with the simplicity of machines without a central core. An early experiment of this type[dubious ] in the 1970s was Trisops. (Trisops fired two theta-pinch rings towards each other.)

Magnetic fusion energy[edit]

All of these devices have faced considerable problems being scaled up and in their approach toward the Lawson criterion. One researcher has described the magnetic confinement problem in simple terms, likening it to squeezing a balloon – the air will always attempt to "pop out" somewhere else. Turbulence in the plasma has proven to be a major problem, causing the plasma to escape the confinement area, and potentially touch the walls of the container. If this happens, a process known as "sputtering", high-mass particles from the container (often steel and other metals) are mixed into the fusion fuel, lowering its temperature.

In 1997, scientists at the Joint European Torus (JET) facilities in the UK produced 16 megawatts of fusion power. Scientists can now exercise a measure of control over plasma turbulence and resultant energy leakage, long considered an unavoidable and intractable feature of plasmas. There is increased optimism that the plasma pressure above which the plasma disassembles can now be made large enough to sustain a fusion reaction rate acceptable for a power plant.[2] Electromagnetic waves can be injected and steered to manipulate the paths of plasma particles and then to produce the large electrical currents necessary to produce the magnetic fields to confine the plasma.[citation needed] These and other control capabilities have come from advances in basic understanding of plasma science in such areas as plasma turbulence, plasma macroscopic stability, and plasma wave propagation. Much of this progress has been achieved with a particular emphasis on the tokamak.

See also[edit]

References[edit]

  1. ^ JET chronology
  2. ^ ITER Physics Basis Editors (1999). "Chapter 6: Plasma auxiliary heating and current drive". Nucl. Fusion. ITER Physics Expert Group on Energetic Particles, Heating and Current drive. 39: 2495. 

External links[edit]

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