Near-field behavior of electrified jet under moving substrate constrains

We investigate the dynamics and shapes of electrified jet deposited onto a moving substrate in near-field electrospinning. At low speed, drag effect imposes on the jet and makes it buckling to a ‘heel’. As the ‘heel’ continues to move far away, a restoring force is accumulated until it is large enough to make an ‘out of the plane deformation’, which will also introduce torsion for the jet and turns it into a rotation state. When the speed increases, stretching effect makes jet drawing to a stable catenary shape. The ‘heel’ is a transition stage between catenary and rotation state due to the buckling of the jet. Moreover, the transformation from the ‘heel’ to ‘catenary’ is validated by modeling the jet as electrified filament. The simulation results show that the speed brings the pulling force exerted on the jet tail and it only depends on the substrate speed. The works provide a better understanding the effect mechanism of the substrate speed on the fiber morphology.