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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.