Optimization of airflow field via solution blowing for chitosan/PEO nanofiber formation

In this paper, a method combining the orthogonal array design and the numerical simulation is proposed to optimize the geometry parameters of the solution blowing nozzles. The centerline velocity is used to evaluate the performance of the nozzle and the characteristics of airflow fields are calculated. Three geometry parameters of the nozzle: the protrusion length of needle, the diameter of needle and the diameter of nozzle are investigated. The results show that smaller needle diameter and larger nozzle diameter will result in a higher centerline velocity, which is beneficial to fiber attenuation, whereas the effect of needle protrusion length is insignificant. The optimal geometry parameters of the nozzle achieved in this study are that the protrusion length of needle of 5 mm, the diameter of needle of 0.8 mm, and the diameter of nozzle of 4 mm. Furthermore, chitosan/PEO nanofibers are manufactured and studied with different geometry nozzles. This work can provide a better understanding of the controllable fabrication of solution blown nanofibers.