Accession Number : AD0674610

Title :   THE SPM (STOCHASTIC PROCESS METHOD) EQUATION FOR CALCULATING THE SPATIAL VARIATION OF NEUTRON SPECTRA.

Descriptive Note : Rept. for May 59-May 60,

Corporate Author : CONTROL DATA CORP MELVILLE N Y TRG DIV

Personal Author(s) : Klahr,Carl N. ; Zell,H. Julius

Report Date : SEP 1960

Pagination or Media Count : 159

Abstract : The SPM equation is a second order partial differential equation in lethargy (or energy) and spatial coordinates. It promises to describe the slowing down and spatial diffusion of neutrons with sufficient accuracy for shielding problems and for other applications where neutron flux spectra are critical. A primitive SPM with infinite orders of derivatives is first obtained from either the Smoluchowski or Boltzmann equations. It is then truncated after the second order derivatives. The coefficients of two forms of this equation are obtained and suitable boundary conditions are given. A code has been written to solve this equation on the 1103A Univac. Various solutions are given. (Author)

Descriptors :   (*NEUTRON SPECTRUM, *STOCHASTIC PROCESSES), PARTIAL DIFFERENTIAL EQUATIONS, SHIELDING, NEUTRON FLUX, INELASTIC SCATTERING, FISSION, DIFFUSION, NUMERICAL ANALYSIS

Subject Categories : Fission Reactor Physics
      Nuclear Physics & Elementary Particle Physics

Distribution Statement : APPROVED FOR PUBLIC RELEASE