Speaker
Mr
Kazuo YOSHIMURA
(Japan Atomic Energy Agency)
Description
To maintain sodium level inside reactor vessels above cores is essential to keep core-cooling for sodium leakage accidents in loop-type sodium-cooled fast reactors. In the loop-type prototype fast reactor Monju which has three primary heat transport systems (PHTSs), a single coolant leakage accident in a PHTS has been taken into account as a design basis accident (DBA). On the other hand, it is important to investigate that another primary coolant leakage would occur after the first coolant leakage accident as a design extension condition (DEC).
In this presentation, we evaluate multiple primary coolant leakages accidents in Monju with consideration of passive safety features. Concretely speaking, the flow rate and the amount of leakages can be reduced by the effect of the decrease of the cover gas pressure due to lowering reactor coolant level (negative pressure effect). The sodium coolant level necessary for the decay heat removal can be maintained, taking account of the negative pressure effect and other measures.
Country/Int. Organization
JAPAN/Japan Atomic Energy Agency
Primary author
Mr
Kazuo YOSHIMURA
(Japan Atomic Energy Agency)
Co-authors
Mr
Kosuke AIZAWA
(Japan Atomic Energy Agency)
Mr
Makinori IKEDA
(Japan Atomic Energy Agency)
Mr
Yasuhiro ENUMA
(Japan Atomic Energy Agency)