Model enhanced paperboard permeability measurement with aerostatically sealed non-contacting instrument

Paperboard permeability is a crucial quality parameter for various grades of paper and cardboard. Traditionally, the permeability measurements are conducted offline using contacting devices. The present study delved into a non-contact aerostatically sealed measurement method and device.
The investigated method, previously developed by the authors, was improved by introducing an aerostatic seal flow model into the calculation of sample permeability. This flow model enables the calculation of seal exhaust into the measurement volume, directly influencing the measured flow through the sample. The method was compared to a reference measurement with contacting seals and to the simple method of the previous study.
The results show that the improved method has good accuracy. Furthermore, the influence of seal supply pressure is found to be negligible. Thus, the study provides evidence on the feasibility of the measurement method and device.