Simultaneous Solution of Neutron/Thermal-Hydraulic Coupled System Based on Finite Difference Newton-Krylov Method

The Newton-Krylov method is utilized to solve the Neutron/Thermal-Hydraulic coupled system in nuclear reactors which convergence rate is higher than the traditional method. Finite difference method is employed to calculate the Jacobian matrix to avoid the analytical expressions of Jacobian matrix. The sparse pattern of the Jacobian matrix is considered to build a higher efficient algorithm compared with the dense Jacobian matrix. The numerical result shows that the advanced Newton-Krylov method is more efficient than the traditional method for the simplified reactor model.