DCH-2: Results from the second experiment performed in the Surtsey Direct Heating Test Facility

This test involved 80 kg of molten core debris simulant ejected under pressure into a 1:10 linear scale model of a reactor cavity. The apparatus was placed in the Surtsey Direct Heating Test Facility to allow direct measurement of the temperature and pressure rise of the contained atmosphere. The molten material was ejected from the cavity as a dense cloud of particles and gas. The dispersed debris caused a rapid pressurization of the 103-m3 atmosphere. Peak pressures ranged from 0.22 to 0.31 MPa above the ambient level. Peak temperatures were from 7590C to 13350C, with the highest values recorded near the top of the chamber. Much of the debris (∼70%) was found adhered to the top and sides of the steel chamber. The pattern of the retained material suggested that the debris field propagated around the chamber following the contour of the vessel. Aerosol measurements indicated that ∼1% to ∼6.6% of the ejected mass was in the size range less than 10μm aerodynamic diameter. 8 refs., 28 figs., 6 tabs