
Accession Number : AD0663369
Title : ENERGYDEPENDENT NEUTRON TRANSPORT THEORY NEAR A TEMPERATURE DISCONTINUITY,
Corporate Author : RAND CORP SANTA MONICA CALIF
Personal Author(s) : Gritton,Eugene C. ; Leonard,Anthony
Report Date : DEC 1967
Pagination or Media Count : 79
Abstract : An exact solution is obtained for the energydependent Boltzman transport equation for thermal neutrons near a temperature discontinuity. The medium is nonabsorbing and infinite in extent. The method of solution consists of expanding the energytransfer kernel in a degenerate form and then solving directly for the solutions of the resulting homogeneous equation. Both discrete and singular solutions are found. The angular flux is then expanded in terms of a complete set of these solutions. Finally, the expansion coefficients are determined by applying the boundary conditions associated with the temperaturediscontinuity problem. Numerical calculations of both scalar neutron flux and total neutron density are included for various temperature ratios and neutrontomoderator mass ratios. A comparison of the transporttheory results with diffusiontheory results shows that diffusion theory describes the neutron flux quite accurately for small values of temperature discontinuity. Diffusiontheory calculations become less accurate, however, as the higher energy modes become important. (Author)
Descriptors : (*NEUTRON TRANSPORT THEORY, NUMERICAL ANALYSIS), INTEGRAL EQUATIONS, REACTOR MODERATORS, NEUTRON SCATTERING, NEUTRON CROSS SECTIONS, NEUTRON FLUX, THERMAL PROPERTIES
Subject Categories : Fission Reactor Physics
Distribution Statement : APPROVED FOR PUBLIC RELEASE