Analysis and optimization of the film cooling in industrial operating high performance blown film plants based on an integrative and calibrated process model

• Applicant: Professor Dr.-Ing. Johannes Karl Wortberg
• Subject Area: Plastics Engineering
• Term: from 2016 to 2019
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 284379684

Like for any other extrusion process, the blown film extrusion is decisively limited by the provided air cooling capacity. Achievable throughputs can be improved by the optimization of the cooling system to a large extent. The motivation of this research project can be seen in the transfer of results and scientific knowledge, based on two preceding DFG projects, in the computer-aided optimization of cooling systems for laboratory blown film lines to industrial production scale. Besides the improvement of the output, the focus is on the identification of potentials in enhancing the process stability. With regard to remarkable changes in the process boundary conditions, one must now adapt and transfer the developed modelling approaches. This includes on the one hand geometric and on the other hand process-related boundary conditions. Besides the prevailing mass flow rates, cooling air volume flows as well as the flow phenomena, additionally the realistic deformation processes inside the film and the geometrical changes of all active and passive involved cooling components have to be taken into consideration. This included the integration of an internal bubble cooling device inside the process environment. The numerical realization is to be done by using the successfully verified and validated Prozess- and Prognosemodell. The challenge is the realistic computation of the tube formation zone at varying process- and cooling conditions. For this purpose various experimental process conditions have to be recorded, to create the basis for the following calibration process and the examination of the capability in reproducing the process state. After finishing the model calibration and proving the reproducing capabilities, the main emphasis will be on the simulation based realization of system optimization potentials.for high capacity blown film lines with output rates of 1000kg/h and die diameter up to 800mm. Furthermore the available material spectrum has to be extended by new multilayer compounds (3-layers / 5-layers), which have to be taken into account concerning the modeling. In cooperation with the industrial partner, the virtual proven optimization potentials have to be experimentally tested and validated in the industrial production environment, to meet the shared goal of improving the output.

• DFG Programme: Research Grants (Transfer Project)
• Application Partner: Mondi Consumer Packaging Technologies GmbH