Numerical simulation of induction heating in FLiNaK molten salt high temperature testing loop

Background: The graphite pebble test section of FLiNaK molten salt high temperature testing loop was designed to study the heat transfer behavior and corrosion behavior between FLiNaK molten salt and fuel pebbles. In graphite pebble test section, the graphite pebbles are heated using a unique medium frequency inductive heating technique to simulate the heat generation inside the fuel pebbles of Pebble Bed Advanced High Temperature Reactor (PB-AHTR), Purpose: The aim is to study the influence of the induction heating by three kinds of graphite pebbles packing scheme. Methods: Numerical simulation of induction heating using finite element method is implemented and the power loss in graphite pebbles is calculated, and then the three kinds of graphite pebbles packing scheme are compared and analyzed from eddy power loss and power distribution. Results: The results show that the relative axial power distributions of three packing schemes are almost the same and the radial power distribution of the packing scheme with no contact between graphite pebbles in each layer is more uniform than that of other packing schemes. Conclusions: In order to heat graphite pebbles evenly and simulate the heat generation inside fuel pebbles of PB-AHTR better, the packing scheme with no contact between graphite pebbles in each layer is recommended. (authors)