Artigo de peri??dico
Total and partial loss of coolant experiments in an instrumented fuel assembly of IEA-R1 research reactor
Registro en:
0029-5493
363
10.1016/j.nucengdes.2020.110610
0000-0001-9544-4509
75.00
66.17
Autor
MAPRELIAN, EDUARDO
TORRES, WALMIR M.
BELCHIOR JUNIOR, ANTONIO
UMBEHAUN, PEDRO E.
BERRETTA, JOSE R.
SABUNDJIAN, GAIANE
Resumen
The safety of nuclear facilities has been a growing global concern, mainly after the Fukushima nuclear accident.
Studies on nuclear research reactor accidents such as the Loss of Coolant Accident (LOCA), many times considered
a design basis accident, are important for ensure the integrity of the plant. A LOCA may lead to the
partial or complete uncovering of the fuel assemblies and it is necessary to assure the decay heat removal as a
safety condition. This work aimed to perform, in a safe way, partial and complete uncovering experiments for an
Instrumented Fuel Assembly (IFA), in order to measure and compare the actual fuel temperatures behavior for
LOCA in similar conditions to research reactors. A test section for experimental simulation of Loss of Coolant
Accident named STAR was designed and built. The IFA was irradiated in the IEA-R1 core and positioned in the
STAR, which was totally immersed in the reactor pool. Thermocouples were installed in the IFA to measure the
clad and fluid temperatures in several axial and radial positions. Experiments were carried out for five levels of
uncovering of IFA, being one complete uncovering and four partial uncovering, in two different conditions of
decay heat. It was observed that the cases of complete uncovering of the IFA were the most critical ones, that is,
those cases presented higher clad temperatures when compared with partial uncovering cases, for the specific
conditions of heat decay intensity and dissipation analyzed. The maximum temperatures reached in all experiments
were quite below the fuel blister temperature, which is around 500 ??C. The STAR has proven to be a
safe and reliable experimental apparatus for conducting loss of coolant experiments.