Abstract
The airflow field and the heat transfer coefficient on the film were investigated, using a two dimensional plane model experimental apparatus of double bubble tubular blown film process. In the model apparatus, a polyethylene film is radiantly heated and simultaneously cooled by oblique impinging plane air jets. It was found that the heat transfer coefficient on the film obtained from the heat balance equation was less affected by the irradiation from the heater than by the jet velocity. Numerical simulation of the airflow field in the experimental apparatus was carried out, and the predicted velocity distributions of airflow as well as the maximum heat transfer coefficient were found in good agreement with the experimental results. It can be observed that the method of the numerical simulations and experiments of this study are useful to the design and the optimization of film production.
