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November 9–12, 2025
Washington, DC|Washington Hilton
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Fusion Science and Technology
Latest News
High temperature fission chambers engineered for AMR/SMR safety and performance
As the global energy landscape shifts towards safer, smaller, and more flexible nuclear power, Small Modular Reactors (SMRs) and Gen. IV* technologies are at the forefront of innovation. These advanced designs pose new challenges in size, efficiency, and operating environment that traditional instrumentation and control solutions aren’t always designed to handle.
M. Yamada, N. Pomphrey, A. Morita, Y. Ono, M. Katsurai
Fusion Science and Technology | Volume 27 | Number 3 | April 1995 | Pages 161-168
Overview Paper | doi.org/10.13182/FST95-A11947061
Articles are hosted by Taylor and Francis Online.
We investigate experimentally and theoretically the global MHD characteristics of an ultra-low aspect ratio tokamak (ULART). Since the ULART requires a substantially smaller toroidal field current, Itf, than conventional tokamaks, it has important reactor advantages. By fully utilizing the TS-3 merging spheromak facility with a slender center conductor, we have carried out an experimental study of the ultra-low aspect ratio tokamak with aspect ratio reaching as low as 1.05. The ULART is found to be similar to the spheromak in its strong paramagnetism and magnetic helical pitch. In this extreme limit, we investigate the transition of the spheromak (qa = 0, Itf = 0) to a ULART plasma (qa = 5–20, Itf < Ip). It is observed that a small current at the center conductor can significantly improve the overall stability of the formed plasmas by effectively stabilizing the tilt mode. We identify a threshold of Itf << Ip with qcyl(a) << 1 for global tilt/shift modes. This initial observation is in agreement with a global MHD theory.
