Release of Metallic Fission Products from Multilayered Coated Particles

Publisher Website
Google Scholar
Abstract
A model simulating the in-pile release of metallic fission products from a batch of coated fuel particles is based on a solution of the transient Fick’s diffusion equation in a nonhomogeneous medium. It is developed in two stages. First, some representative analytic solutions for a single birth pulse in a single particle are numerically tabulated as functions of nondimensional parameters. Second, the solution for a history of continuously varying source, temperature, and particle failure fraction is obtained by interpolation and superposition. This permits use of the method as an efficient source subroutine in full-core release problems. The large number of physical parameters in the model provides adaptability in correlating and extrapolating experimental results. By using numerical examples, the model was shown to account for the following phenomena: recoil, transient diffusion response, transition from the intact to the failed state, and the effect of various rate-limiting mechanisms on the release.

This publication has 2 references indexed in Scilit: