This report presents data from the Unblocked Bundle, Forced and Gravity Reflood Task of the Full-Length Emergency Core Heat Transfer Separate Effects and Systems Effects Tests (FLECHT SEASET) program. The tests consisted of forced and gravity reflood experiments and steam cooling tests, using electrical heater rods to simulate current nuclear fuel arrays (similar to Westinghouse 17 x 17 assemblies) of PWR and PWR fuel vendors. Data obtained include rod clad temperatures, turnaround and quench times, heat transfer coefficients, inlet flooding rates, overall mass balance, differential pressures and calculated void fractions in the test section, thimble wall and steam temperatures, and exhaust steam and liquid carryover rates.

This report presents data from the Unblocked Bundle, Forced and Gravity Reflood Task of the Full-Length Emergency Core Heat Transfer Separate Effects and Systems Effects Tests (FLECHT SEASET) program. The tests consisted of forced and gravity reflood experiments and steam cooling tests, using electrical heater rods to simulate current nuclear fuel arrays (similar to Westinghouse 17 x 17 assemblies) of PWR and PWR fuel vendors. Data obtained include rod clad temperatures, turnaround and quench times, heat transfer coefficients, inlet flooding rates, overall mass balance, differential pressures and calculated void fractions in the test section, thimble wall and steam temperatures, and exhaust steam and liquid carryover rates.