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Transport Calculations In Particle-Loaded Media, Gary J. Scrivner

Nuclear Engineering ETDs

Particle-loaded materials are sometimes used for radiation shielding. In many cases shielding calculations, performed with the assumption of a homogeneous medium having the appropriate ratio of particle-to-matrix material, are grossly inadequate. The exact distribution of particles within such materials is probabilistic in nature, and, therefore quantities, such as the transmitted flux, become random variables. To reasonably evaluate the effectiveness of this type shielding, one must obtain the expected values and corresponding standard deviations of those quantities of interest.

In this dissertation, two models of a particle-loaded shield are investigated. The first is an artificial material postulated to consist of constant-thickness …

Prompt Neutron Decay Constants In A Reflected Fast Burst Reactor, Charles Clayton Price

Nuclear Engineering ETDs

A mathematical model describing the kinetic response of a reflected fast burst reactor is developed using point reac­tor theory. The equations of the model are used to derive a reflected inhour relationship and a two region Rossi-alpha equation.

The model is investigated for three reactor-reflector configurations; the bare reactor, the reactor with a radially symmetric steel reflector, and a reactor with a radially sym­metric polyethylene reflector. This investigation includes the results of a calculational study using Monte-Carlo tech­niques and an experimental program using Rossi-alpha, pulsed neutron, and reactor burst techniques on the Sandia Pulsed Reactor SPR II.

A Type I …