Nonlinear Coarse Mesh Transport Using the Jacobian-Free Newton-Krylov Method

Abstract

This paper presents a nonlinear formulation of a coarse mesh transport method based on work performed in recent years at Georgia Tech[1, 2]. In the original formulation, a global problem is decomposed into local problems for which response functions are computed with the fission source treated implicitly. A global solution is found via outer iterations on the global eigenvalue and inner iterations on the lo-cal boundary conditions.By casting the problem in a nonlinear form,robust nonlinear solvers can be employed,which offer super linear convergence and may be easier to parallelize.