Core burn-up calculation was performed and result shows that all 9 assemblies each containing 28 fuel rods with 7.0 wt% Gd2O3 is the best option for this reactor concept from view point of change of k-eff and power peaking. Preliminary steady-state single-channel thermal hydraulic analysis is performed. The result shows that it is possible to remove heat from the core under 1 atm pressure.