A passive system can provide engineered safety features enhancing safety system reliability and plant simplicty. The Gravity Driven Cooling System (GDCS) provides the emergency coolant following a LOCA by gravity and the Passive Containment Cooling System (PCCS) removes the decay heat without any power-actuated active devices and any operator actions. Toshiba has conducted a test program which was planned by Toshiba and GE to demonstrate the technical feasibility of the passive safety system using an integral system test facility GIRAFFE. The GIRAFFE system test results have shown that the GDCS injection is achieved smoothly in the course of a LOCA and the GDCS has a capability sufficient to keep the core covered by two-phase mixture following an LOCA. In addition, it has been shown that the PCCS automatically starts to remove the decay heat when the GDCS water pool is completely drained and the containment pressure begins to increase.
展开▼
