Bubble dynamics with aerosol in swarm flow during pool scrubbing

We improve the model for the validity confirmation of the severe accidents predictive code such as MELCOR code under the present conditions. The aim of the present study is to clarify Flow structure of gas phase jet with pool scrubbing to improve the MELCOR. We injected gas phase jet into a water cylinder with various flow rate. And the gas flow structure is observed via, a high speed camera in detail. At the test section, a backlight method with a high-speed video camera and a LED lighting system was applied. Test section is filled with water of 1000 mm depth. It was visualized for each 200 mm in height direction of the test section. The bubble size and aspect ratio are measured by the observed images. As a result of comparisons between flow model in MELCOR code and experimental data, Bubble of the experimental were found to be more flattened than the model. In a draft paper, we will describes the velocity of a rising bubble and flow structure estimated by the observed images. In order to understand the flow structure, we also measure of void fraction distribution and bubble velocity in a test section using a wire-mesh sensor (WMS). (author)