The US Department of Energy (DOE) Princeton Plasma Physics Laboratory (PPPL) is collaborating with private industry on cutting-edge fusion research aimed at obtaining commercial fusion energy. This work, enabled through a public-private DOE grant program, supports efforts to develop high-performance fusion grade plasmas. In one such project, PPPL is working in collaboration with MIT’s Plasma Science and Fusion Center (PSFC) and Commonwealth Fusion Systems, a start-up spun from MIT that is developing a tokamak fusion device called SPARC. “
The goal of the project is to predict the leakage of fast “alpha” particles arising during fusion reactions in SPARC, given the size and potential misalignment of the superconducting magnets that define the plasma. These particles can form a large-scale self-heating or “burning plasma” that fuels fusion reactions. The development of burning plasma is a major scientific goal for fusion energy research. However, leakage of alpha particles can slow or stop the production of fusion energy and damage the interior of the spark facility.
New superconducting magnets
Key features of the spark machine include its compact size and powerful magnetic fields that enable the ability of new superconducting magnets to operate in higher fields and strain than existing superconducting magnets. These features will enable the design and construction of smaller and less expensive fusion facilities, as described in recent publications by the SPARC team – assuming that the fast alpha particles formed in fusion reactions are long-lived to keep the plasma warm. Can occur.
PPPL physicist Gerrit Kraemer said, “Our research suggests that they may be the ones who participate in the project through the DOE Innovation Network for Fusion Energy (Info) program. The two-year program, called PPPL physicist Ahmed Diallo serves as Deputy Director, aims to accelerate the development of the private sector of fusion energy through partnerships with national laboratories.
“We found that alpha particles are actually well-limited in spark design,” said Kramer, a paper co-author Journal of plasma physics This suggests the conclusion. He worked closely with lead author Steven Scott, a consultant at Commonwealth Fusion Systems and a long-time physicist at PPPL.
Kramer used the SPIRAL computer code developed in PPPL to confirm the particle. “The code, which simulates wavy patterns, or waves, in a magnetic field that can allow sharp particles to escape, showed good confinement and lack of damage to SPARC’s walls,” Kramer said. In addition, he said, “The SPIRAL code agreed well with the ASCOT code from Finland. While the two codes are completely different, the results were similar.”
The findings brought Scott happiness. “It is gratifying to see computational validation of our understanding of rip-induced damage,” he said, “ever since I studied the issue experimentally in the early 1980s for my doctoral dissertation.”
Fusion reactions combine light elements in the form of plasma – the hot, charged state of matter composed of free electrons and atomic nuclei, or ions, which comprise 99 percent of the visible universe – to generate massive amounts of energy. Scientists around the world are trying to create fusion as an almost unlimited source of electricity to generate electricity.
Kremer and colleagues noted that the misalignment of spark magnets would increase the wave-induced losses of fusion particles, leading to an increase in walls. Their calculations should provide the main guidance to the SPARC engineering team as to how well the magnets should be aligned to avoid excessive power loss and wall damage. Properly aligned magnets will enable the study of plasma self-heating for the first time and the development of advanced techniques for plasma control in future fusion power plants.