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Fusion Science and Technology
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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.
F. Malvagi, G. C. Pomraning, M. Sammartino
Nuclear Science and Engineering | Volume 112 | Number 3 | November 1992 | Pages 199-214
Technical Paper | doi.org/10.13182/NSE92-A29069
Articles are hosted by Taylor and Francis Online.
We consider the problem of neutral particle transport in a stochastic Markovian mixture consisting of an arbitrary number M of immiscible fluids. The Liouville master equation is used to obtain a model for the ensemble-averaged angular flux. This model consists of M coupled transport equations. If the absorption, internal source, and temporal and spatial gradients are assumed small, this transport description can be reduced to a diffusive description. Depending upon the scaling of the Markovian transition lengths, this diffusive limit consists of either a single diffusion equation or a set of M coupled diffusion equations. The asymptotic analysis is also used to derive appropriate initial and boundary conditions for each diffusion equation.