The Correlation between Pressure Drop in Acetate Tow Filters and their Varying Diameters/Über die Beziehungen zwischen den Zugwiderständen von Acetatfiltern und ihren Durchmessern

In order to convert the pressure drop by calculation in cigarette filters of equal length and varying diameter made out of identical acetate tow two premises have to be considered:

1. The filters have the same density;

2. The filters contain the same weight of filament. In filters with the same density a theoretical exponent ε = 2.0 is deduced. As a practical result of the figures collected, ε = 2.06 is to be regarded as the most probable value. This value rises slightly when the densities of the filters compared are not absolutely identical.

For filters with the same material (filament)-weight, the application of the Hagen-Poiseuille law can be queried, and an exponent ε > 4 deduced by means of a model idea. Practical calculation demonstrates that ε varies between 7-8 and 4-5, depending on the differences in diameter, whereby a greater difference results in a smaller ε.