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Fusion Science and Technology
Latest News
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.
S. Van Criekingen, E. E. Lewis, R. Beauwens
Nuclear Science and Engineering | Volume 152 | Number 2 | February 2006 | Pages 149-163
Technical Paper | doi.org/10.13182/NSE06-1
Articles are hosted by Taylor and Francis Online.
A mixed-hybrid treatment of the spatial variables of the within-group neutron transport equation generalizes existing mixed and hybrid methods, combining their attractive features: the simultaneous approximation of even- and odd-parity angular flux components and the use of Lagrange multipliers to enforce interface continuity. A finite element spatial discretization and spherical harmonic angular expansions are used. We discuss rank conditions for the proposed methods and provide a new derivation of the Rumyantsev interface conditions. Even- and odd-parity interface continuity properties corresponding to these Rumyantsev conditions are established. We examine inclusion conditions and the interaction of the primal/dual distinction due to the spatial variable with the even/odd-order spherical harmonic approximation distinction due to the angular variable. Numerical solutions for both even- and odd-order spherical harmonic approximations are presented, and a promising enclosing property is observed in our results.