14 DAY TRIAL // Keeping the flow of plasma – an electrically-charged stream of gas heated at millions of degrees – has been a major obstacle in the path of developing a sustainable nuclear fusion reaction, as turbulences and drops in temperature interfered with the difficult process of merging the similarly-charged nuclei of two heavy atoms. Scientists at MIT managed to devise a way of keeping the gas moving inside the reactors and to reduce turbulences as well.
Radio waves prove to have a direct effect on the way the plasma flows inside the donut-shaped reactor. Maintaining a stable and steady flow is very difficult, because colder walls force the hot gases to become turbulent and break their circular motion patterns. But the science team proved that harnessing radio-frequency waves and directing them at the plasma flow in a specific manner could stabilize it and make it "tamer."
This could pave the way to a faster implementation of this type of technology, although the researchers in charge of the project warn that some time will still have to pass before a viable plant is established. For their study, MIT Plasma Science and Fusion Center (PSFC) physicist, Earl Marmar, division head of the Alcator Project, and researchers Yijun Lin and John Rice used the Alcator C-Mod fusion reactor, one of the largest in the world, which is owned solely by the Massachusetts Institute of Technology.
Nuclear fusion offers a great deal of promises for the future, in terms of energy production and consumption. The resources required for this type of technology to operate are abundant, and the world could get rid of its dependency on radioactive uranium. Instead, tritium and deuterium would be used inside reactors, where they would be collided one against the other, a process that would release enormous amounts of energy.
"We've been looking for this effect for many years. Finally, the conditions were just right. Our results are just in time [for ITER]," says Lin. The International Thermonuclear Experimental Reactor, now under construction in France, will closely resemble Alcator C-Mod, with the only difference being the fact that the first will be about 10 times as big.
"There's been a lot of progress. We're learning a lot more about the details of how these things work," Marmar says.