(Presented at the International Conference on Mathematics and Computational Methods applied to Nuclear Science and Engineering M&C 2013, Sun Valley, Idaho, 2013)

An analysis based on a coupling between the currently available thermal-hydraulics and neutronics codes is an attractive option for dynamic simulation of nuclear power plant transients in terms of developmental cost. The currently adopted temporal coupling scheme is a simple operator-splitting with synchronous time step where the splitting is based on the physics solved by each code. This scheme is known to degrade the overall temporal convergence of the coupled solution. That is, a very small time step size is required to reach an acceptable solution. In this presentation, a simple modification on the temporal coupling scheme based on a time-projection scheme of a solution (i.e., power) is proposed and tested on two different nuclear power plant transients. It is shown that the modification is able to improve the convergence of the coupled calculation.

May 08, 2013