Physicists have figured out how to keep a fusion reactor from exploding

© Photo : ITERПроцесс build ITERPhysicists have figured out how to keep a fusion reactor from exploding© Photo : ITER

British physicists found that the behavior of electron beams inside the «donut» fusion reactor, and understand how to avoid them «escape» from the chamber and subsequent explosion of the reactor, according to an article published in the journal Physical Review Letters.

«If we can slow down these escaped electrons, then we will make a big step towards the creation of full-fledged fusion reactors. Given that the other options we have virtually no fusion looks especially attractive because we can use a simple sea water to produce huge amounts of energy,» says Linnaeus, Hesslow (Linnea Hesslow) from Technological University of Chalmers in Gothenburg (Sweden).

Currently, scientists are seriously considering two types of fusion reactors, the tokamak and the stellarator. Conceptually they are similar: high temperature plasma in them is not the walls of the chamber, and magnetic field. In a tokamak this effect is achieved by passing a current through the plasma, which causes her to shrink into a kind of bagel in the presence of a powerful magnetic field. Stellarator, in turn, operates on several different principles, and the behavior of plasma in it depends exclusively on the operation of the magnetic coils, so it has a kind of «exhaust donut».

The idea of the tokamak is now considered more promising, and it is the basis of the international project ITER, which for several decades is based in France, with the participation of scientists from Russia, EU, USA, China and other countries.

The main problem of the tokamak, it tells Hesslow, is that these reactors can actually explode at any moment. According to scientists, inside the tokamak there may be strong local electric field that will accelerate beams of electrons to such high speeds that they will be able to «break through» the magnetic field that holds the plasma reactor from escaping, and destroy the magnets and the walls of the reactor.

Such fears long enough to hold physicists from long-term and large-scale experiments with tokamaks, which slows down the process of disclosure of the secrets of fusion.

Hesslow, and her colleagues propose to solve this problem, slowing the electrons rather simple way, using heavy ions and atoms of noble gases as a kind of «breakwaters».

By studying how electrons interact with different ions, the researchers drew attention to the fact that their collisions with the nuclei of heavy elements is much stronger change their behavior than the theory predicts. This gave them the idea that the atoms of noble elements previously considered undesirable «debris» in the fuel tokamak, can be used as natural inhibitors of electrons.

To test this idea, physicists have created a computer model of a thermonuclear reactor that takes into account how collisions with heavy ions retard the flow «cascading» of electrons. Their calculations showed that the addition of a small number of atoms of neon or argon in the outer part of the ring of the tokamak, where they will be ionized only partially, or environment is special «pillows» with the atoms of these gases, can protect the reactor from destruction.

«Many people believe that ITER will soon be launched, but in fact, we will be easier to fly to Mars than to build a stable fusion reactor. You need to understand that we are trying to «tame» the energy of the stars here on Earth, and this task will require a lot of time. So I hope that these studies will receive all the necessary resources, we will be able to find a final solution to the energy issue in the future,» says Cheslow.