回転円すいを用いた揚水現象における揚水開始回転数と粘度および浸水量の関係

抄録

It is confirmed that a cone rotating at the liquid surface causes pumping-up of liquid, where the cone is immersed by the top upside down. If the rotation rate exceeds a critical threshold, the pumping-up phenomena occur. The flow of the pumping-up phenomena is classified into two patterns such as film-wise and filament-wise. The critical threshold of the rotation rate and the resultant flow pattern depend on mainly the viscosity, immersed diameter of the cone and angle of cone. We will try to obtain a correlation of rotation rate, viscosity, immersed diameter and angle of cone on the threshold of pumping-up phenomena in order to elucidate the pumping-up mechanism. It is found that there are three categories depending on the viscosity classified as film-wise pumping-up region for the low viscosity, filament-wise pumping-up one for the high viscosity, and no pumping-up phenomenon occurs for intermediate viscosity.