Volumetric Ratio
Ratio of the actual fiber volume to the total volume occupied by the yarn structure determines the porosity of a textile strand. Laboratory analysis measures the amount of air trapped between filaments within a given diameter. A higher packing fraction indicates a more compact yarn with less space for air or moisture between the fibers.
Fiber Density
Radial compression during the spinning process forces the individual filaments into a tighter arrangement at the yarn core. This compaction is influenced by the amount of twist applied and the tension on the spinning line. Denser packing results in a thinner yarn for a given weight per kilometer and increases the hardness of the material.
Dye Absorption
Fluid permeability decreases as the density of the fiber arrangement increases within the strand. High values for this ratio restrict the flow of liquid through the yarn during package dyeing. This resistance can lead to uneven color distribution if the packing fraction is inconsistent throughout the production batch.
Structural Limit
Mechanical properties of the finished fabric are tied to the internal geometry of the yarn. A loosely packed structure provides better thermal insulation but offers less resistance to abrasion. Physical limits on how close fibers can sit prevent this ratio from ever reaching a value of one.
