Development of A Coupled Neutron Kinetics And Thermal Hydraulics Code With 3-D Two Group Neutron Kinetics Solver and OpenFOAM by Adding Feedback of Coolant Temperature in Calculation of Cross Section Using DRAGON for Pressurized Heavy Water Reactor

A loosely coupled reactor is subject to local perturbations due to reactivity device movement that affects the neutron kinetics in a local region of the reactor core. Pressurized Heavy Water Reactor (PHWR) has the additional feature of on power refuelling. The local perturbations introduced by refuelling or by reactivity device movement are reflected in the core neutronics after a finite amount of time. The local perturbation causes changes in coolant temperature and density which in turn affects the neutron kinetics in a feedback loop. It is important for safe reactor operation that the effects introduced due to reactivity device movement or due to refuelling are captured in the neutron kinetics calculations of the core. In order to calculate the effects of perturbations mentioned above we have developed a coupled neutron kinetics and thermal hydraulics code - TRIVENI-OpenFOAM. We are using the coolant and fuel temperature feedback in generating cross section library using DRAGON for neutron kinetics calculations. Our code TRIVENI-OpenFOAM is a complete software package where cross section generation, 3-D two group neutron kinetics and thermal hydraulics feedback for coolant and fuel temperature is done in a single code set.