X-TREAM project: Task 1a - Survey of the different numerical algorithms used in present computer codes - Core simulators and core thermal-hydraulics
Nowadays, the precise modeling of a nuclear reactor core is a challenge. This task involves several aspects, from the computational power needed to perform simulations, to the physics and analysis of the outcome. The need to better understand the physical phenomena is a critical issue in order to quantify and qualify nuclear safety parameters. Currently, substantial research has been done in order to optimize the prediction capabilities of coupled codes. The understanding of the multi-physics of coupled codes is also essential because of the strong coupling between the neutronics and the thermal-hydraulics. In this report a state of the art of current coupled codes is presented. The purpose of this is to present the main algorithms that independent and coupled codes use. By doing that, a better understanding of the numerical schemes is achieved, providing a consistent knowledge in order to select an appropriate algorithm to be implemented. This is the foundation of the X-TREAM project, which final objective is the improvement on the numerical algorithms used in coupled calculations.