Abstract
The best-estimate code TRACE is validated with the stability database of SIRIUS-N Facility at low pressure. The SIRIUS-N facility simulates thermal-hydraulics of the economic simplified BWR (ESBWR) Numerical results exhibits flashing-induced density wave oscillation characteristics, since the oscillation period correlates well with single-phase liquid transit time through the chimney region regardless of the system pressure, inlet subcooling and heat flux Unlike Type-I and II density wave oscillations, the inlet or exit throttling does not affect stability boundary and oscillation amplitude of flashing-induced density wave oscillations significantly. Stability maps in reference to the subcooling and heat flux obtained from the TRACE code agrees with those of the experimental data at low subcooling region, though instability observed in the lower heat flux and higher subcooling region from the stability limit of the experiment.
