Alternative operating conditions for the Modular Helium Reactor

In this study, alternative operating conditions for the Modular Helium Reactor (MHR) were investigated to increase coolant outlet temperature above 850 °C, while keeping the peak fuel temperature below acceptable level at normal operation. Parametric thermal–hydraulic simulations were carried out by using Computational Fluid Dynamics software ANSYS 13.0 CFD FLUENT. The simulated geometry was chosen as an Equivalent Cylinder Model. The porous media approach has been applied to model the complex structure in the core. The study began with an analysis of the current 600 MWt GT-MHR (Gas Turbine-Modular Helium Reactor). The numerical model was validated by other studies. Then, three alternative operating conditions were simulated: (1) with a coolant inlet temperature of 491 °C, a coolant flow rate of 226 kg/s, (2) with a coolant inlet temperature of 641 °C, a coolant flow rate of 320 kg/s, (3) with a coolant inlet temperature of 590 °C, a coolant flow rate of 320 kg/s. The results show that a MHR with these alternative operating conditions have a coolant outlet temperatures about 1000 °C.