Heat transfer and pressure drop characteristics of molten fluoride salt in circular pipe

FLiNaK salt, eutectic mixture of fluorides of lithium, sodium and potassium, is a potential candidate coolant for high temperature reactors (HTRs). In this paper, a CFD analysis has been performed to study the heat transfer and pressure drop characteristics of FLiNaK salt flowing in a circular pipe for various regimes of flow. Simulation is performed with the help of in-house developed CFD code, NAFA. The calculated local Nusselt number (Nu) and friction factor along the pipe have been compared with the available correlations. The dependence of Nusselt number on Reynolds number (Re) has also been predicted and compared. Pressure drop along the pipe has been compared with various correlations. This study shows that the considered correlations for heat transfer and pressure drop are suitable to predict the heat transfer and pressure drop behavior of FLiNaK salt.