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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. N. Cramer
Nuclear Science and Engineering | Volume 141 | Number 3 | July 2002 | Pages 252-271
Technical Paper | doi.org/10.13182/NSE02-A2281
Articles are hosted by Taylor and Francis Online.
Radiation transport integrals containing both forward and adjoint fluxes are amenable to solution by the method of correlated coupling. Existing methods for surface integral coupling of forward and adjoint histories have been extended to volumetric coupling. Within the context of standard Monte Carlo usage, these integral solutions are exact, and the application to perturbation analysis requires no approximation. Coupled forward-adjoint history pairs are initiated at points selected uniformly in the perturbed volume. The energy and angular dependence of each history is dictated by the difference operator of the forward and adjoint transport equations, one equation for the perturbed system and one for the unperturbed system. The volume integral is accumulated as these history pairs score in the respective source or response regions. Some simple systems are analyzed showing that the new method gives comparable results, and a lower variance, as for existing methods. A review of current correlated coupling methodology is given, and suggestions for further study are outlined.