Coupling of Neutronics and Thermal-Hydraulic of CANDU Fuel Management Program and Modification of Time-averaged Model

In this paper, a nonlinear iteration semi-analytic nodal method to solve the diffusion equation and a steady-state single channel thermal-hydraulic code are developed and integrated in the package FMPHWR to realize the coupling of neutronics and thermal-hydraulic. Based on the experiences from PWR, a similar cross-section parameterized method to be used in CANDU is proposed to consider the feedbacks of local parameters. A modified time-averaged model is proposed on the basis of the traditional one. The numerical results show that FMPHWR has superior computational accuracy.