We all know that plasma has many advantages in the application of technology. But we cannot ignore its shortcomings. The editor below sorts out some of the instabilities of the plasma.

Plasma instability (regardless of macroscopic or microscopic) can also be classified by the driving energy that causes it. Such as current instability caused by magnetic energy; exchange instability caused by expansion energy when plasma expands to a weak magnetic field; drift instability caused by plasma expansion energy caused by density and temperature gradient; non-Maxwell distribution or pressure anisotropy Speed ​​space instability caused by free energy corresponding to the opposite sex, etc.

Various types of instabilities in the plasma can cause the escape of charged particles or an abnormal increase in the transport coefficient, destroy the confinement of the plasma or limit the confinement time. Therefore, studying the various instabilities of plasma, elucidating its physical mechanism, and exploring methods of stabilization has always been a central topic in the study of controlled thermonuclear fusion, and it is also an important content of plasma physics.

If the plasma column is only constrained by the angular magnetic field generated by the longitudinal current in it, after a slight disturbance, the inward magnetic pressure at the contraction area increases, and it tends to contract, and the inward magnetic pressure at the expansion site decreases, and it tends to expand. It is shaped like a sausage, so it is called the instability of the sausage. It can cut off the plasma and add a longitudinal magnetic field to resist contraction and expansion to make it stable. If the plasma column carrying a strong longitudinal current is slightly bent by the disturbance, the magnetic field of the concave part will increase and the convex part will weaken. The resulting magnetic pressure difference will expand the disturbance, and the plasma column will quickly bend or even form a helix. Twisting instability can be stabilized by a longitudinal magnetic field. If the water is on the top and the oil is on the bottom, the slight disturbance will exchange under the action of gravity. The instability similar to this in the plasma is called exchange instability. The above cases are all macroscopic instability.

This is the instability of some plasmas sorted out by the editor. There are two sides to everything. But the advantages of plasma are obvious enough. Therefore, some unstable factors can be ignored.