Investigations on the phenomenology of ex-vessel core melt behaviour (COMAS)

Generation III pressurized water reactors and China’s nuclear power

“…If reactor core debris penetrates the reactor pressure vessel, it will enter into the spreading area, which spreads the corium in a compartment provided with a protective layer and a special cooling system. The water in the in-containment refueling water storage tank will flow into the compartment and passively submerge the corium (Steinwarz et al, 2001;Wittmaack, 2002;Fischer et al, 2005). To keep the pressure within the containment below the design limit, the active containment heat removal system, which will be cooled by two separate dedicated trains of cooling water system and service water system, is used to cool the containment.…”

Late Containment Failure

“…In the COMAS project conducted at Siempelkamp (Krefeld, Germany), representative corium melts for the EPR were spread at temperatures around 2000 C [74]. The experimental matrix included spreading of melt into 1D-channels (40 cm wide) with different substratum materials (iron, concrete, ceramics) and spreading into a 2D section made of iron.…”

“…A variety of spreading experiments were performed within various projects, such as CORINE (CEA, France), seeFigure 4.27[65], KATS (FZK, Germany)[70], ECOKATS (FZK)[45] [71], VULCANO (CEA, France)[72], FARO (JRC, Italy)[73], and COMAS (Siempelkamp, Germany)[74] and S 3 E (KTH, Sweden). The experiments were performed on ceramic or concrete surfaces 26 Spreading over an inclined plane (left) and over a horizontal plane (right).…”

The VULCANO VE-U7 Corium spreading benchmark

“…melt containing depleted uranium dioxide with the chemical composition prototypic of a hypothetic severe accident scenario, is absolutely necessary in particular to validate results obtained with simulant materials (Piluso et al, 2001). Experiments using prototypic corium have been performed in the CARLA (Steinwarz et al, 2001), FARO and VULCANO spreading facilities.…”