The Solution of the Lambda Modes Problem Using Block Iterative Eigensolvers

Abstract

High efficient methods are required for the computation of several lambda modes associated with the neutron diffusion equation. Multiple iterative eigenvalue solvers have been used to solve this problem. In this work, three different block methods are studied to solve this problem. The first method is a procedure based on the modified block Newton method. The second one is a procedure based on subspace iteration and accelerated with Chebyshev polynomials. Finally, a block inverse-free Krylov subspace method is analyzed with different preconditioners. Two benchmark problems are studied illustrating the convergence properties and the effectiveness of the methods proposed.