Flow blockage heat transfer in the FLECHT-SEASET 21-Rod Bundle tests

A series of single phase steam cooling and two-phase forced and gravity reflood experiments have been conducted in the NRC/EPRI/W FLECHT-SEASET 21-Rod Bundle Program. The objective of these experiments is to examine the local heat transfer effects of rod bundle blockages in single and two-phase flow. The question to be answered in whether the local heat transfer effects are significantly different in blocked bundle rod arrays as compared to an unblocked reference bundle at the same conditions. Various combinations of blockage shapes and axial blockage distributions have been examined in the 21-rod bundle program which are unique to this program. Detailed rod temperature and vapor temperature measurements were made to assess the local heat transfer effects of the blockages relative to an unblocked reference test. Both single phase and two-phase forced reflood heat transfer results are shown