Film flow around a fast rotating roller

In this study, the film thickness around the roller is numerically estimated using the volume of fluid (VOF) method to clarify the film-formation process around the rotating roller. Parametric studies were performed to compare the effects of ink properties (viscosity, surface tension) and operational conditions (roller rotation speed, initial immersed angle) on film thickness. The viscosity of the ink and the speed of rotation of the roller were found to be the dominant factors that determine the ink film thickness. In addition, a correlation equation is proposed to predict the thickness of the ink film around a printing roller rotating at a speed of 20–30 rad/s, as a function of angular position, angular velocity, and viscosity.