A New Data-Driven ATHLET – ANSYS CFD Coupling Method for Efficient Simulation of Nuclear Power Plant Circuits

A new data-driven coupling method between the system code ATHLET and ANSYS CFX was developed. The new approach allows for coupled simulations of single and two-phase flow with heat transfer and transport of tracer concentration. Any number of coupling interfaces can be defined with the aid of a graphical user interface. Two coupling schemes have been implemented: an explicit scheme where the coupling variables are exchanged at the end of each CFD time step and a semi-implicit scheme in which the variable exchange is performed for each iteration within each time step. The coupling method was validated with measured data from a single-phase double T-junction mixing experiment. The results of the coupled simulation for the double T-junction case, where 3-D effects are very important, were found in excellent agreement with the experimental data. The semi-implicit scheme was found numerically more accurate and stable than the explicit scheme.