Development of a Real-time Core Thermal-hydraulics Model for SMART Simulator

In this paper, 58-channel model is developed and proposed as the subchannel model to satisfy these requirements for MATRA-SSIM code of the SMART simulator. The 58-subchannel model for the SMART simulator is proposed and validated. It is shown that the 58-subchannel model can produce multi-channel and single channel result, simultaneously, without an extra input or modification of source code. The 58-subchannel model will be used to a real-time core thermal-hydraulics model for the SMART simulator whose robustness is improved with a capability of single channel switching option. A multi-purpose best-estimate simulator for SMART is being developed for utilizing in design improvement, operator training, and evaluation of the impact of passive safety system to the performance of SMART. MATRA-SSIM(MATRA SMART SIMulator) code is a part of simulator engine software which has a function of calculating core thermal hydraulic fields during the simulated transients as well as provide TH parameters to the neutron kinetics code for reactivity feedback calculations. The SMART simulator has a requirement of a real time simulation capability. Moreover, each code loaded in SMART simulator has to preserve the robustness of simulation. Therefore, it is necessary to develop an appropriate subchannel model to satisfy the requirement of the real time simulation and have the robustness, simultaneously