A team of Princeton University physicists and engineers has built a twisting fusion reactor called a stellarator that uses permanent magnets, demonstrating a potentially cost-effective way to build powerful machines. Their experiment, called MUSE, relies on 3D printing and off-the-shelf parts.
Nuclear fusion, the reaction that powers stars like the sun, produces large amounts of energy by merging atoms (not to be confused with nuclear fission, which produces less energy by splitting atoms). Nuclear fission is the reaction at the heart of modern nuclear reactors that power the electrical grid. Scientists have yet to crack the code on nuclear fusion as an energy source.Even if long-sought goals are achieved, scaling technology and Making it commercially viable is its own beast.
A stellarator is a churro-shaped device that contains high-temperature plasma that can be tuned to promote conditions for fusion reactions. They are similar to tokamak, A donut-shaped device that runs a fusion reaction. Tokamak relies on solenoids, they are magnets that carry electric current. Muse is different.
“Using permanent magnets is a completely new way to design stellarators,” explain Tony Qian, a physicist at Princeton University and first author of two papers published in Nature Journal of Plasma Physics and nuclear fusion The design of the MUSE experiment is described. “This technology allows us to quickly test new plasma confinement ideas and easily build new devices.”
Permanent magnets do not require electric current to generate a magnetic field and can be purchased directly. The MUSE experiment glued such magnets to 3D-printed casings.
“I realized that even if they were placed side by side with other magnets, rare earth permanent magnets could generate and maintain the magnetic field needed to confine the plasma so that the fusion reaction could occur,” said Michael Zanes, a research scientist at the university’s Plasma Physics Laboratory Michael Zarnstorff said. MUSE project principal investigator in a press release. “That’s the characteristic that makes this technology work.”
Last year, scientists at the Department of Energy’s Lawrence Livermore National Laboratory (LLNL) Achieving break-even in fusion reactions; That is A reaction that produces more energy than is required to power it. However, this honor ignores the “wall power” required to elicit a response. In other words, there is still a long, long road ahead.
LLNL’s breakthrough was achieved by shining a powerful laser onto a cluster of atoms, a process that is different from the plasma-based fusion reactions that occur in tokamak and stellarators.Make some small adjustments to the device, such as using permanent magnets in MUSE or Upgraded tungsten diverter in KSTAR tokamakmaking it easier for scientists to replicate experimental setups and conduct experiments at high temperatures for longer periods of time.
Taken together, these innovations will enable scientists to more Plasmas are within reach, and maybe – just maybe – the goal of usable and scalable fusion energy can be achieved.