Novel hybrid scheme to compute several dominant eigenmodes for reactor analysis problems Conference Paper uri icon

abstract

  • The lack of cost-effective numerical schemes to obtain several dominant eigenpairs accurately has been a cause of concern in "modal analysis" for predicting BWR instability patterns. In this paper, we introduce novel hybrid schemes with inexact Newton method at its heart to create a very accurate eigensolver that is consistent and accurate for unsymmetric, generalized eigenvalue problems occurring in nuclear reactor analysis. Results from test problems to quantify the efficiency and accuracy of the scheme prove that quadratic convergence of Newton iteration is guaranteed when good initial guess for the eigenmode is provided. For a given discretization, the eigenpairs are obtained to machine precision with the hybrid scheme and efficiency of the solver can be further improved by using ILU or multigrid, multilevel Preconditioners for the loss matrix.

author list (cited authors)

  • Mahadevan, V., & Ragusa, J.

publication date

  • December 2008