Fractal theory use in setting of wool yarn

People usually explain wool fiber chemical setting principle from the micro perspective of molecule,while neglecting the effect on shape-setting caused by interaction between fiber assemblies.This paper uses fractal theory,from the macro-perspective view of interaction between fiber and fiber to analyze the principle of wool setting,the fractal dimension analysis and the multi-fractal spectrum analysis of setting principle are given.The results show that with the setting time increases,yarn fractal dimension first increases,then decreases,showing yarn structure tends to rules.Multi-fractal spectrum width decreasing shows that the yarn structure gradually becomes even.The difference of spectrum function remains always greater than zero,indicating that the dominant is larger unit,the long fiber in yarn mechanical performance plays the dominant role.