Authors: C.G. du Toit, W. Boyes, J.F. Slabber
Year: 2025
Industry: Nuclear & SMR
Keywords: Use FSE, Steady state, RCCS
ABSTRACT
The thermal-hydraulic behavior of the Advanced Micro Reactor (AMR) is modelled considering two options using the system code Flownex SE. In option 1 the coolant flows from the inlet to the upper plenum (UP) through risers placed in the outer reflector (OR). In option 2 the coolant flows through the gap between the core barrel (CB) and the reactor pressure vessel (RPV). Under steady-state conditions the maximum fuel and graphite temperatures are 1032.4oC and 809.0oC for option 1 respectively, whilst the corresponding temperatures for option 2 are 1012.4oC and 786.8oC respectively. The maximum temperatures of the OR, CB and RPV for options 1 and 2 are respectively 397.9oC, 357.7oC, 252.4oC and 593.2oC, 440.9oC, 315.6oC. Under Depressurized Loss of Forced Cooling (DLOFC) conditions that heat rejected by the reactor cavity cooling system (RCCS) in option 1 rises from 86.1 kW to a maximum of 109 kW, whilst in the case of option 2 it rises from 142.6 kW to a maximum of 148.4 kW. The maximum rate at which heat is released by the solids is 47.2 kW in option 1, whilst for option 2 the rate is 78.7 kW.