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- Un sphéromak est un arrangement de plasma prenant la forme d'un vortex toroïdal (un tube courbé refermé sur lui-même). Le terme sphéromak n'est pas un synonyme de tokamak sphérique. Le sphéromak contient de grands courants électriques internes avec les champs magnétiques associés. Ils sont disposés de manière que les forces magnétohydrodynamiques à l'intérieur du sphéromak soient presque équilibrées, ce qui permet d'obtenir des temps de confinement de longue durée (microsecondes) sans champs externes. Les sphéromaks appartiennent à un type de configuration de plasma appelé tores compacts ou compact toroid. (fr)
- 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 useful in the laboratory setting, and spheromak guns are relatively common in astrophysics labs. These devices are often, confusingly, referred to simply as "spheromaks" as well; the term has two meanings. Spheromaks have been proposed as a magnetic fusion energy concept due to their long confinement times, which was on the same order as the best tokamaks when they were first studied. Although they had some successes during the 1970s and '80s, these small and lower-energy devices had limited performance and most spheromak research ended when fusion funding was dramatically curtailed in the late 1980s. However, in the late 1990s research demonstrated that hotter spheromaks have better confinement times, and this led to a second wave of spheromak machines. Spheromaks have also been used to inject plasma into a bigger magnetic confinement experiment like a tokamak. (en)
- Lo spheromak è una configurazione del campo magnetico in cui la componente toroidale e quella poloidale hanno la stessa intensità. Lo spheromak è impiegato nell'ambito della ricerca sui reattori nucleari a fusione a confinamento magnetico, in questa modalità è possibile mantenere il plasma di fusione in equilibrio magnetoidrodinamico. La stabilizzazione del campo magnetico è largamente autogenerata attraverso le correnti del plasma arrivando a un plasma stabile e tipicamente toroidale. Il termine spheromak è anche usato per riferirsi alla configurazione stessa del plasma. Un dispositivo spheromak è, come per la configurazione a campo invertito, considerato un tipo di toroide compatta. A differenza dei tokamak e degli stellarator, i dispositivi di questo tipo hanno un design più semplice e richiedono un solo set di bobine magnetiche. (it)
- スフェロマック型 (Spheromak) は磁場閉じ込め方式核融合の一形式。 (ja)
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