Evaluation of Air Entrainment between a Paper Web and a Roller

In offset press or paper machine, a paper web runs on many rollers, and a thin film of air is formed by air entrainment between the roller and the web. The film of air influences the function of each roller, e.g. heat transfer, etc. In this research, experiments and theoretical analysis of air entrainment, considering the permeability of paper web, have been conducted. Based on the theory of hydrodynamic lubrication, the air film was calculated numerically, and the results showed good agreement with the experiment. the results showed good agreement with the experiment.