Analysis and Parallel Implementation of Transient Thermal Feedback in Neutron Kinetics Calculation

Transient computing scheme named K-MOD has been designed that time-discrete is carried out by implicit Runge-Kutta method, and coarse nodal method is used for neutronics calculation at present. During transient calculation, thermal feedback is introduced to update the cross-section to approximate the transient behavior of the real core based on the method of interpolation on state-points. Corresponding thermal feedback for coupling calculation is programmed and analyzed, and parallel computing is introduced to enhance efficiencies of single-disciplinary codes and data coupling section. Problem of rod insertion and lift in real core of PWR (Pressurized Water Reactor) is tested and compared. The results show that K-MOD is in good agreement with the results of SMART software in both fixed time step and adaptive time step. And the parallel efficiency is also explained.