D102 液中に噴出する不足膨張気体噴流の可視化(OS10 混相流動)

抄録

When a heat exchanger in a Fast Breeder Reactor cracks, a sodium-water reaction occurs. Highly pressurized water or steam escapes into the surrounding liquid sodium from the crack. The release of steam into the liquid sodium media is a two-phase flow with an underexpansion. Several studies have examined only the underexpansion of the gas-gas phase. However, there are few reports on the underexpansion of the gas-liquid phase. In this study quantitative measurement was carried out for the purpose of revealing the flow with the underexpanded gas jet injected into water. The gas jet distance L and the expansion angle θ were then obtained from averaged images of a high-speed camera. L and θ increased approximately linearly with increasing pressure. The entrainment velocity and the velocity of entrained water droplets into the gas jet were obtained by PIV.