[en] This is the second Yayoi study meeting on drawing gas in from free liquid surface. In two years after the first meeting, the considerable development has been observed in the research on drawing cover gas in the coolant of fast reactors. Based on those results, this time, the topic was limited to drawing gas in from the botom of concave vortices. The prospect of coping with the various types of drawing gas in from free liquid surface by design has been obtained, and drawing gas in from the bottom of concave vortices is the problem being left to the last. The feature of this study meeting is the interchange of the researchers in various fields. The publications this time are centering around atomic energy and civil engineering, and the special lecture on tornado was added. Lectures were given on the development of the demonstration FBR and drawing-in of gas, the structure for preventing drawing-in of gas for reactor vessels, the development of the structure for preventing drawing-in of gas for IHX, the effect of physical property values on the growth of gas cores and drawing-in of gas, research on drawing-in of gas by water channels, the characteristics of flow velocity distribution of laminar concave vortices, drawing-in of gas from the bottom of swirling vortices, numerical simulation of drawing-in of gas by swirling vortices and so on. (K.I.)