Abstract
A steam jet flow injected into a large bulk space has been simulated by using the MARS code, an integrated best-estimate nuclear thermo-hydraulics analysis code. MARS code has been constructed by KAERI by a coupling and modernization of the RELAP5 and COBRA-TF codes. The multi-dimensional analysis capability of the MARS code has been assessed by comparing it's results to the results of the OECD-SETH PANDA experiment. PANDA facility consists of two large vessels connected by a horizontal pipe. The volume of a vessel is approximately 90 m^3. A steam jet is injected into the vessel through a 0.153m diameter nozzle located at a middle height of the vessel. Among the various series of PANDA tests, the condensation phenomena involved tests are selected and simulated by the MARS code. The whole vessel and the connecting pipe are modeled as a Cartesian multi-dimensional grid. In spite of a few discrepancies and a restriction of the grid size, the MARS code results show a promising performance for predicting the temperature and steam concentration distributions in a large bulk space.
