Acceleration of the Analytic Function Expansion Nodal method by two-factortwo-node nonlinear iteration

A nonlinear iterative scheme is developed to reduce the computing time of t he Analytic Function Expansion Nodal (AFEN) method and is applied to three test problems, including a mixed-oxide fuel problem. The new, nonlinear sch eme is based on solving two-node problems and using two nonlinear correctio n factors at every interface instead of one factor, as in the conventional scheme. The use of two correction factors provides higher-order accurate in terface fluxes as well as currents, which are used as the boundary conditio ns of the two-node problem. The numerical results show that this new nonlin ear scheme reproduces the sane solution as that of the original AFEN method and that the computing time is significantly reduced in comparison with th e original AFEN method.