A new shape factor measure for characterizing the cross-section of profiled fiber

It is an important topic to characterize the cross-sectional shape of profiled fiber for quality control of textiles and performance design. In this paper, we propos e a new measure of the shape factor, which can be used to characterize the cross-sections of profiled fibers. Different from the existing indices of the shape factor which are based on the ratio of the radii of circumscribed and inscribed circles, the proposed measure uses the shape information residing in the boundary of profiled fiber cross-sections. It is defined as the coefficient of variation of the area sequence in the cross-sectional plane at each angular interval. The capacity of this measure is validated by various examples, which also indicates that the defined measure can distinguish the discrepancy degree between fiber cross-section and the area equivalent circle. It is robust and applicable to any arbitrary shape with solid cross-section, no matter whether it is convex or concave.