CORA-13 experiment on severe fuel damage, core degradation and quench

1 - Description of test facility: CORA- test facility operated at Kernforschungszentrum Karlsruhe serving to study the behaviour of PWR fuel elements under severe accident conditions: - fuel rod bundle with heated and unheated rods under controlled thermal-hydraulic boundary conditions, high temperature radiation shield surrounding the bundle; - heated fuel rods consist of 6 mm diameter tungsten rod surrounded by UO2 annular pellets; - two absorber rods added to the bundle to simulate interaction of fuel rods with absorber rod materials; - steam supply to provide superheated steam; - refill or quench phase added. Scaling Information: heated length of rods 1,000 mm, rod dimensions and pitch corresponding to original PWR fuel. 2 - Description of test: Severe core damage experiment with quenching, of a full length simulated fuel bundle, heated with internal tungsten heaters. Investigations of the material relocation dynamics, quench phenomena and hydrogen generation. The out-of-pile experiment CORA-13 was executed in November 1990. In the experiments the decay heat is simulated by electrical heating. Great emphasis is given to the fact that the test bundles contain all materials used in light-water reactor fuel elements, to investigate the different material interactions. Pellets, cladding, grid spacers, absorber rods and the pertinent guide tubes are typical of those of commercial LWRs with respect to their compositions and radial dimensions