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In transition: Commercializing fusion power
Commercial fusion power is closer than ever. There are now around 30 U.S. fusion companies, several of which claim to be on track to connect to the grid as early as the 2030s.
Tokamak and laser inertial confinement approaches benefit from decades of research at facilities such as the National Ignition Facility (NIF) at Lawrence Livermore National Laboratory and ITER, with alternative concepts including stellarator, magnetic mirror, and Z-pinch confinement also making notable progress as private and government funding for fusion increases.
Robert E. Rothe, D. C. Hunt
Nuclear Science and Engineering | Volume 54 | Number 3 | July 1974 | Pages 360-366
Technical Note | doi.org/10.13182/NSE74-A23427
Articles are hosted by Taylor and Francis Online.
Thirteen previously unpublished critical measurements on enriched (93.16 wt% 235U) uranium metal spheres, which are radially but not axially centered in cylinders of enriched (93.16 wt% 235U) uranium solution, are presented and compared with the results of Monte Carlo calculations. The average reproduction factor calculated for experimentally critical systems was k = 0.989, and this bias showed no systematic variation with the amount the sphere was displaced from center. The sphere size was increased, keeping other parameters constant, until criticality was calculated, at which point the average sphere radius and mass were 2.8 and 8.8%, respectively, greater than the experimental cases. For a given solution cylinder, the minimum critical metal sphere mass occurs when the sphere is centered in the solution. The increase in this critical mass with position along the cylinder axis is also presented parametric in two tank diameters and five solution concentrations. For like asymmetries and at the same concentration, a greater change in the critical sphere mass with position is seen for tanks of large diameter than for smaller tanks. If the tank diameter is fixed, the greater change occurs for solution of high uranium concentration.