Paper Title
Correlation of Rotation Rate, Viscosity and Immersed Diameter on the Threshold of Pumping-up Phenomena using Rotating Cones

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 and immersed diameter of the cone. So, we investigate the critical rotation rate where the pumping-up occurs by changing the concentration of glycerol aqueous solution as working fluid and the immersed diameter. 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. Eventually, we will try to obtain a correlation of rotation rate, viscosity and immersed diameter on the threshold of pumping-up phenomena in order to elucidate the pumping-up mechanism. Keywords - Rotating Cone, High Viscosity Solution, Pumping-up Behavior, Rayleigh-Taylor Instability