Airflow through fiber plugs. Part I: Review of theory and its limitations

Abstract

We have analyzed the extensive data provided by Lord on the rate of air flow through plugs of cotton and a number of other fibers without lumena. Some of these data comprise over a 200-fold range of air flow. We have shown that the data do not conform to the formulas for air flow through fiber plugs as developed by Lord himself. The data can be better fitted by a family of three-parameter equations, but it is difficult to relate these parameters to the physical properties of fibers, such as linear density, form factor, and specific volume. In the case of cotton, one of the parameters is indeed proportional to the product of linear density and maturity ratio, but there appears to be no way of disentangling these two from a knowledge of the other parameters governing air flow. We show a way out of this difficulty by postulating a new approach, which is described in Part II of this paper.