QUEOS, an experimental investigation of the premixing phase with hot spheres

Abstract A total of 60 experiments with hot spheres, to investigate the premixing phase of a steam explosion, have been performed in the QUEOS facility at Forschungszentrum Karlsruhe (FZK). Here, the data of seven experiments are presented using three types of spheres at 1800 K and total volumes of ≈2, and 4l, respectively. The sphere jet plunging into the water had a diameter of 10 cm and a length between 60 and 120 cm. The average solid volume fraction was ≈25%. These relatively long jets and high particle volume fractions show a different behavior in the water, compared to the 18 cm wide short pours of a first series of QUEOS experiments. They are also unlike experiments performed in other facilities with much lower particle volume fractions. High speed films were taken, pressures, water temperatures and the steaming rate were measured.