NC State
P. Shallhorn and N. Gurnagul. A simple model of the air permeability of paper. In Advances in Pulp and Paper Research, Oxford 2009, Trans. of the XIVth Fund. Res. Symp. Oxford, 2009, (S.J. I’Anson, ed.), pp 475–490, FRC, Manchester, 2018.


We have developed a simple model of the air permeability of paper and shown that it is in reasonable agreement with experimental results for softwood chemical pulps. The permeability is given as a function of fibre external height and width and fibre volume fraction including the lumen volume if present. The most important conclusion from the model is that the average fibre thickness in the paper is the critical fibre property controlling air permeability. In fact, the theory predicts that the sheet permeability is roughly proportional to the fourth power of the fibre thickness.

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