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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.
K. W. Burn
Nuclear Science and Engineering | Volume 125 | Number 2 | February 1997 | Pages 128-170
Technical Paper | doi.org/10.13182/NSE97-A24262
Articles are hosted by Taylor and Francis Online.
A weight-dependent capability is inserted into the direct statistical approach (DSA) to optimize splitting and Russian roulette (RR) parameters in Monte Carlo particle transport calculations. In the new model, splitting or RR is carried out on a progenitor arriving at a surface in such a way that the weight of the progeny is fixed (for the particular surface). Thus, the model is named the DSA weight tine model. In the presence of weight-dependent games, all components of the second moment, and the time, are not separable. In the absence of weight-dependent games, the component of the second moment describing the weight-dependent splitting or RR is still not separable. Two approximations are examined to render this component separable under these circumstances. One of these approximations, named the noninteger approximation, looks promising. The new DSA model with the noninteger approximation is tested on four sample problems. Comparisons with the previous weight-independent DSA model and with the MCNP (version 4a) weight window generator are made.