Abstract: By turning a rod covered with a viscous liquid (e.g.. honey), some of the liquid can be retained on the rod without dripping. For this phenomenon, most previous theories are based on the N-S equations, which cannot clearly explain the physical mechanisms of the phenomenon. In this paper, a simple theoretical model of the phenomenon dominated by viscous force, centrifugal force, gravity and surface tension is obtained through a simple force analysis and a method similar to dimensional analysis, which avoids the complex and lengthy solution of the hydrodynamic equations; Experimentally, self-consistent experimental data are obtained through the construction of a stable device and reasonable control of variables. The experimental results are in good contrast with the theory, and the physical mechanisms and key factors of the non-dripping of viscous liquid on the rotating rod are explained intuitively. The theoretical analysis is in good agreement with the experimental results, and the physical nature and key factors for the non-dripping of viscous liquids on rotating rods are explained intuitively.

Key words:  , fluid mechanics, coating flow, viscous liquid, surface tension, centrifugal effect